When I worked for IDE at IAD, my sup would let me take a tug around the airport to snap pictures of whatever I found to be interesting that day. I got some great pictures of some SPs, a Tu-154 for the Yuri Gagarin Cosmonaut School, some VC-10s, and all kinds of other more normal things around Dulles.
If I wasn't out taking pictures, I was probably doing a relocation under tow (something you should check into if you're interested in being a pilot - you'll get limited training in how to get the plane ready to be safely moved and talk on the radios...it passes the time, too, but I did it more because I really enjoyed it), or doing something else productive, like getting the next bank's bag sheets out on the desk, doing a bug wash, filling the water or dumping the lav (requested or not).
If nothing productive was left and I wasn't out filling my camera's memory card, I'd probably just grab a book, or sit around telling stories with the other ramp guys. My sup had the most hilarious stories.