[chrisper]

I'd also say that if you are not paid you approach the work differently. Like you can take your time with certain things maybe. A lot less stress, I'd imagine. (Depends on the project obviously. If you get yelled at by Linus, you probably should be more careful!)

[notzorbo3]

True, but expectations are sometimes also higher. Documentation etc has to be of good quality. Packaging. Stuff like that. There's really no comparing it with a paid job IMHO. It's more fun i'd say.