Your favourite games that you could never play more than once?

Me personally, I really like to squeeze out every bit of potential I have to waste time with my games. Its why replay value seems to be such a huge factor in my decision with games. 
 
Some games however, ones that I still found myself enjoying, I could never bring myself to play through again. 
 
Such games as the original BioShock (and the sequel from the looks of things too). Its one of my all time favourite games and with so much versatility with the plasmids, guns and tonics, one would expect that replay value would be fantastically high. But BioShock relied most on its atmosphere and story, once I got all of that I didn't feel much motivation to heading back. Not even to play through again as an anti-social, little sister hating prick. 
 

Folklore
 
Kinda like Bioshock in the way it relied on the story a lot so playing a 2nd time wouldn't have nearly the same impact.

Metal Gear Solid 4. I've technically completed the game twice, but the second play-through was taking turns with me and a mate for his benefit because he doesn't have a PS3. I've tried to play it since and just can't.
 
I feel the same about Bioshock, and it's even carried over to 2. Can't get into that game at all. 
 
I've played parts of Uncharted 2 again since completing it, but never linearly all the way through. The experience first time was epic, and is apparently all I needed from it.

I'm not sure if I've ever really liked a game and not been able to go back through it. There aren't many games where I can immediately do another playthrough 1-2 weeks after finishing it the first time, but usually I'll just wait 4-5 months until I forget 75% of the stuff that happens in the game, then replay it.

Doom 3 might be the game that comes to mind most immediately. I really enjoyed that game, but I've never been able to go back through it.

Either of the Mass Effect games. The story can go many directions but you care about the characters so much you want to close the book on their story and not replay it to look behind the theatrical curtain so to speak.

MGS4. I played that shit like an action movie, I doubt I'd ever relive the same magic twice. (I prefer that)