I have to say, I've been kind of dissapointed by the lack of people who have so much as mentioned FFT. (I didn't read the entire thread, so I might have mispoken there).
Anyway, FFT is my favorite, and I've played through 4,6,7,8, and 9, along with portions of all the rest. The battle system in tactics, which was the primary reason it was made, I suppose, is much more fun/interesting/exciting than those of the other FFs. The job system is an excellent way to build characters, my favorite from all the games. Admittedly, the graphics aren't top notch, but they really fit for the game. And lastly, the storyline is awesome. Its a step away from the other FF stories (no dark, brooding, amnesia-suffering heroes saving the world this time, sorry guys), but I think I got more involved with it than the others, love them though I did. Oh, and as fore as being purely despicable goes, the villian (?) in FFT tops them all. (Can I get a hoo-wah from someone who hates Delita?)