What are some fun things to do while riding besides no-hands?

I ride by bike every day as part of my commute and like to spice it up by riding no handed. It was pretty tricky at first, but I eventually got the hang of it and now it's as easy as riding normally. Then I tried turning no handed - a little bit harder, but not too hard - plus I don't have many opportunities to do it on my route. So I'm wondering, are there any other pointless skills I can learn? Maybe no feet?

Before anyone asks, I only do these things when there is no one else on the road.

Edit: Just remembered, I'm currently trying to get better at coasting slowly without putting my feet down during a light.