I like the pedophile poster idea. Though he won't know why someone did it it would still feel nice.

And though I have spit in someones face +1 for you'll probably cross paths again, but if he hits you with something call 911 and say that you've been attacked and the guy drove off, don't let them know that it is an ongoing dispute, and deny deny deny if he accuses you of starting it a couple weeks ago.