I had a real weakspot for Tf2 surf maps and I don't fully understand why. I think it's partly the fact that this isn't how you're "supposed" to play the game, but is an added bonus that came about by accident.
I'm also not very good at them, I spent far too long on surf_utopia (v3, I think) and only ever got to the end of it once.
I love Small Gods! It's my go-to when people ask which Discworld book they should start with and want a good standalone.
The image of Om, in turtle form, piloting an eagle by biting it's unmentionables to canonball the head priest is fantastic.