I love doing the ATC swaps on Craftster. They're generally quick and easy. They also give me a chance to play around with new techniques that I want to try.
The top one was a requested butterfly theme. The second theme was to create an ATC based on your favorite song without using words. The song I chose was "Songbird" by Oasis. Love that song! They're both very simple ATCs. I just used scrap paper, printed images and stamps. The butterfly antennae is some sort of cord that I glued on there.