The Indy Art Museum is pretty nice, and there are some other museums in Indy that aren't bad. You could also go to Louisville in Kentucky, not sure what's there. If you haven't been to Nashville (Indiana), that's another possibility, it's pretty nice, and you could probably swing by the monastery on the way, they are in the same general direction...if you like hiking you could go out Lake Monroe way and do some of that...if you wanted to be really REALLY adventurous, you could drive to Chicago or Columbus, they're both around 4 hours away...