RPGaDay2015 Part 2 (15-16)
The longest game I've ever played was (QAGS co-founder) Leighton Connor's "Ficton" super-hero game (not to be confused with The Hex Ficton), which I've mentioned here before. It think it lasted around six years, but I'm not sure if it would technically be considered a single campaign; the climax was rooted in stuff that had been there from the beginning, but the PC group changed several times over the course of the game.
The Death Cookie
RPGaDay2015, part 2
Here are my responses to the next two questions.