My two favorite Car Wars experiences:
1) I attended a little con at the University of Michigan (BurCon, I believe), and they ran an event called Bus Wars. Everyone got about an hour to build a university bus stocked to the gills with weaponry, and then we played a huge demolition derby in the North Campus area. The U was erecting a hideous new bell tower on North Campus at that time (it did and still does look like a giant...nevermind), and I remember bonus points were available for anyone who took it out. Great game.
2) I played a large game at home once that involved two teams (two or three people each) -- both of which independently picked the same basic strategy. The strategy was to buy a large number of really crappy cars with ram attachments and stuff them with impact-detonated high explosives -- no armor, of course.
We played cat and mouse for awhile, all getting the feeling that we had hit on the same tactic...until someone decided to just go for broke, and rammed another car. It took about ten minutes to work it out, but the resulting explosion destroyed nearly every car on the map, along with most of the buildings. Sublime.
I think the best part of Car Wars overall is the vehicle construction. Much like BattleTech, designing units is really my favorite aspect of the game -- closely followed by seeing how my designs do on the battlefield, of course.
Edit: I almost forgot my favorite piece of Car Wars minutia, from Murphy's Rules: all Car Wars characters have 3 hit points, and taking 2 points of damage knocks them out; a .357 magnum does 2 points of damage -- which means a character can't commit suicide using one.
