Can't say I played many games where you have a choice of being good or evil, the ones I do remember is Fable and Oblivion, though, in Oblivion your actions don't have much effect on the rest of the playthrough. I tend to be on a good side in games, evil's not really appealing in general to me, the only time I do evil deeds in games is when I'm curious to see what will happen or if I have to.

In Oblivion there's a sidequest where you have to help an old man to collect some fish scales, so he can finally go into retirement with the money scientist will give him for those fish scales. I was curious to see how many gold coins he got so I stole his bag of coins later on, I loaded immediately after that, I felt sorry for the old man (I know it's a game, but still...), and it wasn't a big amount to begin with.