Not exactly a hobby, but years ago I created a series of shareware adventure games for the Mac, which turned out to be reasonably popular. Unfortunately when Apple moved on to OS X, my games got left behind. Well now, after all this time and thanks to the programming skills of a friend, there is now an updated version of one of my games in the Mac App Store! More info and a preview video here:
My apologies in advance if this post is considered inappropriate for the forum, I’m just really excited about this!