Yeah, I went through the entire gamestop listing inventory online of XBox games, tons of stuff under $5. Of course, it's the expensive games I'm really interested in.
I went into one over the weekend and the sales clerk there said that Xbox AND Gameboy Advance would start to be clearanced out about the same time.
I am highly skeptical of the GBA clearance happening any time soon, despite the new DSi not being able to play them. But it would definitely be nice if it did happen. Though there are a ton of good games under $5 already, if you can find them...