Personally I think Krosan Tusker is the best functioning Cycling card... but here's a list of all of them...
Akroma's Blessing
Color= White Type= Instant Cost= 2W ON(U)
Text (ON): Creatures you control gain protection from the color of your choice until end of turn. ; Cycling {W}.
Akroma's Vengeance
Color= White Type= Sorcery Cost= 4WW ON(R)
Text (ON): Destroy all artifacts, creatures, and enchantments. ; Cycling {3}.
Aura Extraction
Color= White Type= Instant Cost= 1W ON(U)
Text (ON): Put target enchantment on top of its owner's library. ; Cycling {2}.
Backslide
Color= Blue Type= Instant Cost= 1U ON(C)
Text (ON): Turn target creature with morph face down. ; Cycling {U}.
Barkhide Mauler
Color= Green Type= Creature - Beast Cost= 4G ON(C)
Text (ON): 4/4. ; Cycling {2}.
Barren Moor
Color= Land Type= Land Cost= None ON(C)
Text (ON): ~this~ comes into play tapped. ; {Tap}: Add {B} to your mana pool. ; Cycling {B}.
Blasted Landscape
Color= Land Type= Land Cost= None US(U)
Text (US+errata): {Tap}: Add one colorless mana to your mana pool. ; Cycling {2}. [Oracle 2000/10/24]
Bloated Toad
Color= Green Type= Creature - Toad Cost= 2G UL(U)
Text (UL): 2/2, Protection from Blue ; Cycling {2}.
Brand
Color= Red Type= Instant Cost= R US(R)
Text (US+errata): Gain control of all permanents you own. (This effect doesn't end at end of turn.) ; Cycling {2}.
Choking Tethers
Color= Blue Type= Instant Cost= 3U ON(C)
Text (ON): Tap up to four target creatures. ; Cycling {1}{U}. ; When you cycle ~this~, you may tap target creature.
Clear
Color= White Type= Instant Cost= 1W US(U)
Text (US): Destroy target enchantment. ; Cycling {2}.
Cloud of Faeries
Color= Blue Type= Creature - Faerie Cost= 1U UL(C)
Text (UL+errata): 1/1, Flying ; When ~this~ comes into play, if you played it from your hand, untap up to two lands. ; Cycling {2}. [Oracle 1999/06/30]
Complicate
Color= Blue Type= Instant Cost= 2U ON(U)
Text (ON): Counter target spell unless its controller pays {3}. ; Cycling {2}{U}. ; When you cycle ~this~, you may counter target spell unless its controller pays {1}.
Darkwatch Elves
Color= Green Type= Creature - Elf Cost= 2G UL(U)
Text (UL): 2/2, Protection from Black ; Cycling {2}.
Death Pulse
Color= Black Type= Instant Cost= 2BB ON(U)
Text (ON): Target creature gets -4/-4 until end of turn. ; Cycling {1}{B}{B}. ; When you cycle ~this~, you may have target creature get -1/-1 until end of turn.
Dirge of Dread
Color= Black Type= Sorcery Cost= 2B ON(C)
Text (ON): All creatures gain fear until end of turn. ; Cycling {1}{B}. ; When you cycle ~this~, you may have target creature gain fear until end of turn.
Disciple of Grace
Color= White Type= Creature - Cleric Cost= 1W US(C)/ON(C)
Text (US/ON): 1/2, Protection from black ; Cycling {2}.
Disciple of Law
Color= White Type= Creature - Cleric Cost= 1W US(C)
Text (US): 1/2, Protection from red ; Cycling {2}.
Disciple of Malice
Color= Black Type= Creature - Cleric Cost= 1B ON(C)
Text (ON): 1/2, Protection from White. ; Cycling {2}.
Drifting Djinn
Color= Blue Type= Creature - Djinn Cost= 4UU US(R)
Text (US+errata): 5/5, Flying. ; At the beginning of your upkeep, sacrifice ~this~ unless you pay {1}{U}. ; Cycling {2}. [Oracle 1999/05/01]
Drifting Meadow
Color= Land Type= Land Cost= None US(C)/AT(F1)/BR(F1)
Text (US): ~this~ comes into play tapped. ; {Tap}: Add {W} to your mana pool. ; Cycling {2}.
Essence Fracture
Color= Blue Type= Sorcery Cost= 3UU ON(U)
Text (ON): Return two target creatures to their owners' hands. ; Cycling {2}{U}.
Expunge
Color= Black Type= Instant Cost= 2B US(C)
Text (US+errata): Destroy target nonartifact, nonblack creature. It can't be regenerated. ; Cycling {2}. [Oracle 1999/05/01]
Fade from Memory
Color= Black Type= Instant Cost= B ON(U)
Text (ON): Remove target card in a graveyard from the game. ; Cycling {B}.
Fend Off
Color= White Type= Instant Cost= 1W UD(C)
Text (UD+errata): Prevent all combat damage that would be dealt by target creature this turn. ; Cycling {2}. [Oracle 2000/10/24]
Flame Jet
Color= Red Type= Sorcery Cost= 1R UD(C)
Text (UD): Cycling {2}. ; ~this~ deals 3 damage to target player.
Fluctuator
Color= Artifact Type= Artifact Cost= 2 US(R)
Text (US): Cycling costs you up to {2} less to play.
Forgotten Cave
Color= Land Type= Land Cost= None ON(C)
Text (ON): ~this~ comes into play tapped. ; {Tap}: Add {R} to your mana pool. ; Cycling {R}.
Hush
Color= Green Type= Sorcery Cost= 3G US(C)
Text (US): Destroy all enchantments. ; Cycling {2}.
Improvised Armor
Color= White Type= Enchant Creature Cost= 3W ON(U)
Text (ON): Enchanted creature gets +2/+5. ; Cycling {3}.
Iron Will
Color= White Type= Instant Cost= W UL(C)
Text (UL): Target creature gets +0/+4 until end of turn. ; Cycling {2}.
Krosan Tusker
Color= Green Type= Creature - Beast Cost= 5GG ON(C)
Text (ON): 6/5. ; Cycling {2}{G}. ; When you cycle ~this~, you may search your library for a basic land card, reveal that card, and put it into your hand. Then shuffle your library.
Lay Waste
Color= Red Type= Sorcery Cost= 3R US(C)/ON(C)
Text (US): Destroy target land. ; Cycling {2}.
Lingering Mirage
Color= Blue Type= Enchant Land Cost= 1U US(U)
Text (US): Enchanted land is an island. ; Cycling {2}.
Lonely Sandbar
Color= Land Type= Land Cost= None ON(C)
Text (ON): ~this~ comes into play tapped. ; {Tap}: Add {U} to your mana pool. ; Cycling {U}.
Lull
Color= Green Type= Instant Cost= 1G US(C)
Text (US+errata): Prevent all combat damage that would be dealt this turn. ; Cycling {2}.
Mage's Guile
Color= Blue Type= Instant Cost= 1U ON(C)
Text (ON): Target creature can't be the target of spells or abilities this turn. ; Cycling {U}.
Miscalculation
Color= Blue Type= Instant Cost= 1U UL(C)
Text (UL+errata): Counter target spell unless its controller pays {2}. ; Cycling {2}. [Oracle 1999/05/01]
Pendrell Drake
Color= Blue Type= Creature - Drake Cost= 3U US(C)
Text (US): 2/3, Flying. ; Cycling {2}.
Polluted Mire
Color= Land Type= Land Cost= None US(C)/AT(F1)/BR(F1)/BD(F1)
Text (US): ~this~ comes into play tapped. ; {Tap}: Add {B} to your mana pool. ; Cycling {2}.
Power Taint
Color= Blue Type= Enchant Enchantment Cost= 1U US(C)
Text (US+errata): At the beginning of the upkeep of enchanted enchantment's controller, that player pays {2} or loses 2 life. ; Cycling {2}.
Primal Boost
Color= Green Type= Instant Cost= 2G ON(U)
Text (ON): Target creature gets +4/+4 until end of turn. ; Cycling {2}{G}. ; When you cycle ~this~, you may have target creature get +1/+1 until end of turn.
Radiant's Judgment
Color= White Type= Instant Cost= 2W UL(C)
Text (UL): Destroy target creature with power 4 or greater. ; Cycling {2}.
Rapid Decay
Color= Black Type= Instant Cost= 1B UD(R)
Text (UD): Cycling {2}. ; Remove from the game up to three target cards in a single graveyard.
Rebuild
Color= Blue Type= Instant Cost= 2U UL(U)
Text (UL+errata): Return all artifacts to their owners' hands. ; Cycling {2}. [Oracle 1999/05/01]
Rejuvenate
Color= Green Type= Sorcery Cost= 3G US(C)
Text (US+errata): You gain 6 life. ; Cycling {2}.
Remote Isle
Color= Land Type= Land Cost= None US(C)/BR(F1)/BD(F1)
Text (US): ~this~ comes into play tapped. ; {Tap}: Add {U} to your mana pool. ; Cycling {2}.
Renewed Faith
Color= White Type= Instant Cost= 2W ON(C)
Text (ON): You gain 6 life. ; Cycling {1}{W}. ; When you cycle ~this~, you may gain 2 life.
Repopulate
Color= Green Type= Instant Cost= 1G UL(C)
Text (UL): Shuffle all creature cards from target player's graveyard into that player's library. ; Cycling {2}.
Rescind
Color= Blue Type= Instant Cost= 1UU US(C)
Text (US+errata): Return target permanent to its owner's hand. ; Cycling {2}. [Oracle 1999/05/01]
Rune of Protection: Artifacts
Color= White Type= Enchantment Cost= 1W US(U)
Text (US+errata): {W}: The next time an artifact source of your choice would deal damage to you this turn, prevent that damage. ; Cycling {2}. [Oracle 1999/05/01]
Rune of Protection: Black
Color= White Type= Enchantment Cost= 1W US(C)
Text (US+errata): {W}: The next time a black source of your choice would deal damage to you this turn, prevent that damage; Cycling {2}. [Oracle 1999/05/01]
Rune of Protection: Blue
Color= White Type= Enchantment Cost= 1W US(C)
Text (US+errata): {W}: The next time a blue source of your choice would deal damage to you this turn, prevent that damage; Cycling {2}. [Oracle 1999/05/01]
Rune of Protection: Green
Color= White Type= Enchantment Cost= 1W US(C)
Text (US+errata): {W}: The next time a green source of your choice would deal damage to you this turn, prevent that damage; Cycling {2}. [Oracle 1999/05/01]
Rune of Protection: Lands
Color= White Type= Enchantment Cost= 1W US(R)
Text (US+errata): {W}: The next time a land source of your choice would deal damage to you this turn, prevent that damage; Cycling {2}. [Oracle 1999/05/01]
Rune of Protection: Red
Color= White Type= Enchantment Cost= 1W US(C)
Text (US+errata): {W}: The next time a red source of your choice would deal damage to you this turn, prevent that damage; Cycling {2}. [Oracle 1999/05/01]
Rune of Protection: White
Color= White Type= Enchantment Cost= 1W US(C)
Text (US+errata): {W}: The next time a white source of your choice would deal damage to you this turn, prevent that damage; Cycling {2}. [Oracle 1999/05/01]
Sandbar Merfolk
Color= Blue Type= Creature - Merfolk Cost= U US(C)
Text (US): 1/1. ; Cycling {2}.
Sandbar Serpent
Color= Blue Type= Creature - Serpent Cost= 4U US(U)
Text (US): 3/4. ; Cycling {2}.
Scrap
Color= Red Type= Instant Cost= 2R US(C)
Text (US): Destroy target artifact. ; Cycling {2}.
Secluded Steppe
Color= Land Type= Land Cost= None ON(C)
Text (ON): ~this~ comes into play tapped. ; {Tap}: Add {W} to your mana pool. ; Cycling {W}.
Shimmering Barrier
Color= White Type= Creature - Wall Cost= 1W US(U)
Text (US): 1/3, First strike. (Walls cannot attack.) ; Cycling {2}.
Sicken
Color= Black Type= Enchant Creature Cost= B US(C)
Text (US): Enchanted creature gets -1/-1. ; Cycling {2}.
Slice and Dice
Color= Red Type= Sorcery Cost= 4RR ON(U)
Text (ON): ~this~ deals 4 damage to each creature. ; Cycling {2}{R}. ; When you cycle ~this~, you may have it deal 1 damage to each creature.
Slippery Karst
Color= Land Type= Land Cost= None US(C)/AT(F1)/BR(F1)/BD(F1)
Text (US): ~this~ comes into play tapped. ; {Tap}: Add {G} to your mana pool. ; Cycling {2}.
Slipstream Eel
Color= Blue Type= Creature - Beast Cost= 5UU ON(C)
Text (ON): 6/6. ; ~this~ can't attack unless defending player controls an island. ; Cycling {1}{U}.
Smoldering Crater
Color= Land Type= Land Cost= None US(C)/AT(F1)/BD(F1)
Text (US): ~this~ comes into play tapped. ; {Tap}: Add {R} to your mana pool. ; Cycling {2}.
Solar Blast
Color= Red Type= Instant Cost= 3R ON(C)
Text (ON): ~this~ deals 3 damage to target creature or player. ; Cycling {1}{R}{R}. ; When you cycle ~this~, you may have it deal 1 damage to target creature or player.
Starstorm
Color= Red Type= Instant Cost= XRR ON(R)
Text (ON): ~this~ deals X damage to each creature. ; Cycling {3}.
Sunfire Balm
Color= White Type= Instant Cost= 2W ON(U)
Text (ON): Prevent the next 4 damage that would be dealt to target creature or player this turn. ; Cycling {1}{W}. ; When you cycle ~this~, you may prevent the next 1 damage that would be dealt to target creature or player this turn.
Swat
Color= Black Type= Instant Cost= 1BB UL(C)/ON(C)
Text (UL/ON): Destroy target creature with power 2 or less. ; Cycling {2}.
Tranquil Thicket
Color= Land Type= Land Cost= None ON(C)
Text (ON): ~this~ comes into play tapped. ; {Tap}: Add {G} to your mana pool. ; Cycling {G}.
Undead Gladiator
Color= Black Type= Creature - Zombie Barbarian Cost= 1BB ON(R)
Text (ON): 3/1. ; {1}{B},Discard a card from your hand: Return ~this~ from your graveyard to your hand. Play this ability only during your upkeep. ; Cycling {1}{B}.
Unearth
Color= Black Type= Sorcery Cost= B UL(C)
Text (UL+errata): Return target creature card with converted mana cost 3 or less from your graveyard to play. ; Cycling {2}. [Oracle 1999/05/01]
Veiled Serpent
Color= Blue Type= Enchantment Cost= 2U US(C)
Text (US+errata): When an opponent plays a spell, if ~this~ is an enchantment, ~this~ becomes a 4/4 Serpent creature. It can't attack unless defending player controls an island. ; Cycling {2}. [Oracle 1999/05/01]
Wild Dogs
Color= Green Type= Creature - Hound Cost= G US(C)
Text (US+errata): 2/1. ; At the beginning of your upkeep, if a player has more life than any other, that player gains control of ~this~. ; Cycling {2}. [Oracle 1999/05/01]
