I don't know what it is about Jeep CJ and Wrangler owners but there seems to exist this kind of brotherhood among us. I have owned my Wrangler now for about five years, and whenever I encounter another Wrangler or CJ driver on the road, the other driver almost always initiates a friendly wave.
Of course when I first realized what was going on - that I had been inducted into this brotherhood by virtue of the fact that I, too, own a Wrangler - I also began to take the initiative and started waving at other Jeep drivers along the beaten path.
Almost without exception, they will give a hearty wave back at me.
The bikers have their wave and I guess we do, too.
Long live the Jeep. :)