Empty consoles.

[Xiahou]

For the PS2, the Fatal Frame series is very good (quite possibly the best scares you'll ever have in a game), Persona 3 and 4 (4 just came out last month) are bargain bin deals and are easily 40+ hours worth of RPG goodness, and Shadow of the Colossus is epic in every way. Katamari Damacy and We <3 Katamari are both quirky and fun. Metal Gear Solid 2: Substance and Metal Gear Solid 3: Subsistence are both recommended (get Substance and Subsistence, not the originals), but be prepared for the beginning of Kojima's patented 60-minute cutscenes.

If you're a Japanese RPG fan, get yourself Persona 3 FES immediately. It sells for $29.99 or less and playing through the game + expansion's storyline can take 120hrs easily. It took me just over 90hrs to win the original story, without the FES content - you can't beat a value like that.

If you want something more off the beaten path, take a look at God Hand - "A ball-bustingly hard game. But fair"
It's a cheesy, quirky beat-em-up with some great old school appeal. The game cracks me up.