Simple Case Mods to Play With

I have a spare Cooler Master Elite 431 sitting in a closet and will eventually end up selling or giving to someone. In the mean time, I thought this would be a good chance to try painting a case, and with white being a popular color I was going to go with that. Aside from painting, are there any other relatively cheap and easy mods that I could play around with?

It depends on your level of creativity, there's a cool channel on YouTube of a guy that custom cases really good.