I, right now, am keeping the games I've bought, played, and beat.

I'm still debating whether I should sell them back to the store for a fraction of the price. (Really small fraction)

I have about 8 games I don't even touch anymore and I'm not sure if I should sell 'em for money to buy a new game.

It seems I would like to have a collection but the older the games get, the less they're worth.

Discuss? 

Yes. Although I've got quite some games I never play anymore, and I'm considering selling them. The not-so good ones, anyway. I'll keep the classics.

nope. It has to be a really replayable game that doesn't take too long to replay.

That is why I only have like 3 Wii games. However, I have played and beat another 15 or so.

Gotta love Ebay.

I feel the same way. If the game is a must have , or has good replay value I keep it, but if you won't play it again and it isn't to good just get rid of it.

No, I never even thought of selling them.
Just played Spyro the other day and lately I've been playing Hot Shots Golf 3.

I have not once sold a game I purchased, I think it's ridiculous.

I keep the timeless gems and sell off the crap. No point in keeping games that wont be revisited at some point in the future. I try to keep a hold of good offline multiplayer games too.

 really.

 I buy games used off Ebay, save about $10 per game. (Every 5th game is free basically)

I resell that game later, anywhere from $5 - $10 less than I paid.  

 In the end I have way more games than most people and spend a fraction of the money I would have by either buying and keeping or renting from blockbuster/hollywood.

Financially speaking I say your method is ridiculous. 

Unless I disliked them I keep them. I play through games numerous times, if I don't like them I'll trade them in or something.

I sold a bunch of gameboy and GBA games, that's about it.