Yeah, this is not something that i would let go. There are a few options, most of which have been noted already, but they all have their consequences (SP?). Since he dont know you, a "suprise" ass beating in a parking lot somewheres at night would work. He would never know who you were. Or you can try to confront him some wheres outside his home, get him good and pissed, let him take the first swing and then proceed to beat his head into the ground. Claim self defense......