For me, it would probably be Azure Dreams. I heard there was a sequal/remake for the GBA/DS? But it was awful - so definitely the PS1 version. It had the monster merging of Jade Cocoon, but a bit more polished? I just remember the monsters looking a bit weird in JD! Plus the randomly generated dungeon running and the town building/improvement. And the challenge of going in at level 1 each time with limited items. Awesome game!

Does it count if they're already doing it? a sequal to Age of Wonders: Shadow Magic - can't wait! There aren't many games that I just fancy replaying randomly - but that is definitely one of them.

Definitely have to agree with Star Ocean - loved all of them! - want more!

With all the mentions of Final Fantasy Tactics, I thought this might interest some people... (if it hasn't already been linked elsewhere).

And Breath of Fire, Vagrant Story.... There are plenty of other games, but these are the ones that come to the top of my mind!