You don't...? Well, you should.
I just wanted to share this site with my visitors. I think it is only open to users in North America though.
Basically it is trading site where you can swap games with other users. Goozex uses a point system for all trades and charges $1 per trade (trade credits). Most new games are around 1000 points and some older games go as low as 100 points. Basically 100 points = $5. If you trade off the games that you don't want and build up a good amount of points then you'll only ever have to spend $1 per trade and pay nothing else (well, except for shipping if you're the one making the game offer).
I've been using Goozex for a few months now with some very good results. Here's a list of games that I have gotten so far:
Mortal Kombat: Shaolin Monks (Xbox) - 100 ptsAnd I only had to trade off just a few newer games to get those (House of the Dead [Wii] and a few others). Still have 1400 points left as well. As you can see, I like to surf the site for older games. To me, you get the best deals with the older titles.
Street Fighter Alpha 3 Max (PSP) - 250 pts
Kameo: Elements of Power (X360) - 250 pts
Turok: Evolution (Xbox) - 100 pts hey, I was curious
Resident Evil 4 Preview Disc (GC) - 100 pts I know, I know...
Yoshi's Island DS (DS) - 300 pts
I usually sell my unwanted games on Half.com, but this site sometimes gives me more value per game. It is most likely a better alternative than Gamestop trades as well.
If you do join then be sure to join through the link above or the link on the right side of the page below so we'll both get an extra 100 points and 1 trade credit on your first positive trade.