I have a really small collection of Playstation games, since I've foolishly sold many of them (that were actually really good and worth keeping) over the years. I'd get stuck on a level, and rather than put it away for awhile or keep trying, I'd sell it and move on to the next game. This was stupid, just because with practice and patience, you can usually get past a difficult part, and it feels more rewarding knowing that you stuck by it.
My biggest blunders were selling Final Fantasy VII (which can go up to a hundred dollars, and this is for a used copy) and Silent Hill (whose value spiked when the movie came out, I don't know if it's still high). Both of them were really good games, and there were plenty of others I sold as well that I shouldn't have.
One of them was Ape Escape, which I just bought again on Amazon. This was a really unappreciated platformer back in the day (that being '99 or 2000). You had to catch monkeys, basically. But it's so fun. And it takes full advantage of the Dual-Shock controller, which was new at that time. You use one analog stick to move, and you use the other to catch monkeys with your net. I think it's more known and respected now, as there have been several sequels on the PS2. It's also been remade for the PSP, I was conflicted between getting this and the one for the PSP, but then I'd have to buy a PSP. Also, more importantly, the PSP doesn't have the 2nd analog stick. That's a major stumbling block.
So, I'm hoping for it to come soon. In the meantime, I'm playing Perfect Dark; I'm stuck on the last level, I'm hellbent on beating the Skedar leader, but it's hard just to get to him. Also, I'm probably going to play FF2 and start trying to level up my skills until Ape Escape gets here.