I have a whole bunch of bumper stickers to design, and I immediately thought of one thing that pisses me off: you're driving, and you want to read the bumper sticker on the car in front of you, but you can't because it's too small. You pull up behind them, you're as close as you could possibly be in traffic, but you still can't read it. So I want to avoid that with these stickers.
Any tips or thoughts about bumper sticker typography beyond the obvious "Make it big and clear"? It's an interesting thing to think about, because it's such a distracting environment for dealing with reading, and a lot of bumper stickers are a full sentence veering towards a full paragraph.