I was reminded of one this morning, and another over the last couple of days:
1) Morons who put HID bulbs in their reflector headlight housings. Without the cutoff of a projector housing you just blind everybody on the road. And why must you always turn your headlights on in broad daylight when you've done that? Are you showing off the fact that you're too cheap and/or too stupid to upgrade your entire headlight like you should? Tools like this are why you have some people trying to ban HID conversions entirely.
2) Putting cones and one of those stupid plastic "caution kids at play" signs in the road does not turn the street into your kid's playground. Either teach your kids to watch out for cars and get the hell out of their way, don't allow them to play in the street at all, or if you can't manage that, keep them inside or in the back yard. The street is there so I can drive to and from my house, not your snotty little kid's powerwheels. Shooting me a dirty look for driving the completely reasonable 25 mph limit past the area you've unilaterally decided is your crotchfruit's personal play area is not going to win me over either.