The people who run the site saw my post and sent me a bunch of the stickers, and The Green Miles went to town:
Bar in Arlington, VA
My favorite moment of the experiment so far came at DC's Shakespeare Theatre. Before the show, The Green Girlfriend came out of the restroom and excitedly said, "There's a 'These Come From Trees' sticker in there!" It felt like we were part of the League of Shadows or something and one of our members had already left our mark.
As I mentioned a while back, there's not a whole lot of difference between using a paper towels and an air dryer, but there's no need to waste either. This is a very cool, very subtle reminder for people to think about how the little things that they do can impact the environment.