I really don't do too terribly much on the decks forum (perhaps once a week I'll post on someone's deck). and there's a reason for that.
If you check out my little deck/dice/sleeve/spare card carrying box, you can see that I've pretty much represented the CPA in there. Let me explain how I mean:
On the far right side of my box is my current netdeck. This is a deck I've built straight off of a major site by a major player.
Before you start flaming me, let me tell you why I, of all people, have a netdeck in my deckbox. It's very simple. I enjoy playing in tournaments. Where I play, a large number of the other tournament players are playing the "dominant" deck of the time (I'm currently packing Zvi's Fires whatever the heck you call it). As such, when I build a deck intended for tournament play. I want to test it thoroughly, and sometimes Apprentice just doesn't work well enough. As such, its very easy to get one of the other random players there (sadly few casual players) to play Fires against my invention.
So why am I bringing it along? Simlple, I know for a FACT that that deck will comprise somewhere about 50-60% of the field come Friday. It's deplorable, but it lets me build decks that specifically humiliate the big deck of the day. I recommend this to anyone here trying to break into tournament play. Build a netdeck that's going to be making a huge showing at the next showing, and play your own deck against it. My record has grown to a large enough stage that other players are (painfully) slowly starting to build their own decks. This lets me, in turn, play more casual games.
To the left of stupid netdeck is my current tournament deck. I don't play it unless I'm testing it.
To the left of my tourney deck is a set of 40 empty cardsleeves, specifically for drafts. I prefer shuffling with sleeves, so I simply re-use them for each draft.
To the left of the sleeves is my current casual T2 duel deck. It's always something weird that doesn't always work, but it's a blast when it does. This gets the majority of my attention.
To the left of my casual T2 duel deck are several draft sets of Invasion block. Drafting is huge where I am, and I can go through 4 draft sets per week - easily. Currently, I'm packing 6 packs of Invasion, 6 of Planeshift, and one Invasion tournament pack. That'd be 1 sealed deck and 3 drafts.
To the left of my draft sets is my current extended deck. There's something about old school black control (Skirge!). I always pack this just in case I meet someone who wants to play extended.
Next up comes my life counter, one of those nifty Flying Tricycle thingys (excellent, everyone should have one), and of course I have the Black mana symbol on it. Additionally come a whole bunch of assorted tokens and counters for fading, kicker, +1/+1, and that whole thing. They also tend to be black.
Second to last comes my land sets, 30 of each basic. Because you never know.
Finally comes my multiplayer deck, chock full of wackiness that wreaks havoc on multiple foes (Unnerve, Grave pact, Thrasing Wumpus, Syphon Soul, and other bits of wackiness) I generally play 5 Star (amazingly, mages of each of the other 4 colors are also around from time to time. When we're all there, we all actually have decks built for just such occasions)
Hopefully this helps explain the CPA a bit better. We're basically like my deckbox, players who play anything from Type 2 to Chaos, 5 Star, Drafts, Extended, and beyond. We're willing to play anything, so long as we can have fun, regardless of how the other players look at it.
And that, my friend, is the true definition of casual.
