Ok, I don't know what rock I've been living under. But today I found a link from our friends at GetDeb to a new beta site called PlayDeb.
MAN! I've not seen a more comprehensive selection of games for Linux in a long time. Anyone who tells you there are no games for Linux is lying or very uneducated.
This site actually adds a repository so you can add/remove games the same way you would any other application. As well, it should follow that when they repackage new versions of the games, they would come down via the normal system updates.
There is a fab list of the games available on the front page of the site. They range from First Person Shooters, to car racing and puzzle type games. Some are simple, some are complex. It really is a great list if you are tired of snake and mahjong games.
Don't just take my word for it, check it out! And remember to play as hard as you geek.