Simply had to be getting Sonic Adventure DX over Heroes. (both GC) It was about 10 or something bucks
I'm trying to give SADX a chance, but I've only beaten Windy Valley and Emerald Coast and I haven't found out what the hell I'm supposed to do next. x_x
To be EXTREMELY honest, I also have to say all the Half-Life 2 games (HL2 itself and its episodes) for ~6 bucks during that summer sale. I just can't seem to enjoy the games at all, and I might even have to say I never really liked the first ones (HL1 and its expansions) at all either.

Quest 64, for the Nintendo 64.

I was a big RPG nerd in high school and my brother and I had most of what was worth getting for our SNES (Chrono Trigger, Illusion of Gaia, Secret of Evermore, etc). When we upgraded to the N64, however, there were no RPGs available for quite some time after launch. When Quest 64 was announced, we preordered it immediately, devoured every Nintendo Power article about it and daydreamed about how amazing it would be to play a FULLY 3-D (!!!) RPG.

When our copy finally arrived, we very quickly realized we had been hookwinked. The environments were nowhere near as detailed as those from the best SNES RPGs, the "characters" and "story" were as substantial as cotton candy and the combat system required as much thought as tic-tac-toe. To add insult to injury, we had been forced to buy a memory card because the game didn't support saving to the cartridge, even though that was supposedly one of the reasons stuck with cartridges instead of switching to CDs, making this the most expensive game we ever bought. I don't think we spent more than five hours on it, and eventually we just *gave* it to a pawn shop. I couldn't bring myself to accept money from them for it, knowing how terrible it was.