i JUST registered because i saw how interesting this post was. at first, i couldn't come up with any games, but after reading all the posts i remember playing some great games. i actually still have most of these games and my saved data on memory cards. thanks to all those who already mentioned these games, brings back good memories.
Star Ocean: Second Story - first game that i spent +150 hours, and i still haven't beaten it. so much to do, customizations and exploration. i've always wanted to play the 3rd one, but never got to it.
Breath of Fire 3: one of the first rpg games i truly enjoyed. i believe i quit playing for a couple years and then, finally, beat it. i played part of the 4th one(and i think i have it, somewhere) and i didn't like it.
Final Fantasy 8,9, and 10, but especially
Final Fantasy 7: i remember playing this game when i didn't have PS, at my cousin's house. i died about 5 times at the first boss (i was like 9 years old, i don't think i even knew what a rpg was at that time) and never got past it. couple years later i picked it up with a friend and i played it on and off for years. imo its the best FF i've played (i haven't played the ones before it, FF1-FF6).
Suikoden II: i think it was Suikoden II, i can't remember. it was on PS and it was one of those games that i played hours on end. i remember going crazy when i got my own castle, lol. it was freakin awesome. unfortunately, i don't think i finished it.
Xenogears: awesome game, i loved the whole atmosphere of the game. i don't know why i hear bad things about it.
Legend of Legaia: another awesome game. as a previous poster noted, this game was unique with its creative battle system and unique story-line. the mist and those things that attached to your arm (i totally forget the details), oh yeah and those trees.
Diablo II and Diablo II: LoD
the game i have played the longest(about 4 years). the game seems so limited with only 5 Acts and point-and-click game style. but, surprisingly i found it to be fun rushing people from Act 1 to 5, normal to hell; creating a new character, which led to a totally different style of fighting; pwning ppl in the face in duels; using hacked items(when just about everyone else was using them) like hexes, AO_ith(not sure how it was spelled) equipment, white rings, and etc. before the 1.10 patch... good times.
KotOR I and II: when i began playing this game, i thought it was going to be just another rpg. man, was i in for a surprise. i was into both these games for awhile, trying out different mods and such.
Elder Scrolls IV: Oblivion
i got the game a couple weeks ago. i think im over 100 hours into it(bah im too lazy to check). interestingly, that same cousin who had the PS(when i first played FF7) actually had Oblivion and i decided to try it out after watching him play. i totally got into it and decided to get it(luckily the GotY edition was out!)
Mass Effect: this is the reason why i have my xbox360 right now, seriously. when my cousin(yes, the same one) came over for the weekend i became obsessed with it and about a month later i got my xbox. i might've burned myself out on this game because i played so much within two weeks of getting it. but i love how it resembles KotOR, brings back memories.
i vaguely remember Chronotrigger and Chronocross. i remember in one of them you could run away from boss fights!
i probably forgot a bunch more games that i've played. this is all it for now.