The death of the jewel case. Compact Disks, CD-Roms, DVDs, Blu-Ray disks...all of these types of media are the same damn shape, unchanged for the past 25 years. So why isn't there one type of carrying case to rule them all? I can't find a particular disk that I've put away because they are stacked in 20 different piles or shelves since there's no way to put them all together in one easy-to-find place. It takes me 15-60 minutes, and I'm usually obsessively organized. I'm about ready to give up on rotating media.
DJs that talk over music. I know this this is pretty much a Caribbean thing, but since the reggae/soca/dance hall stations here are the last bastion of unique and mostly unspoilt music left that don't bear the hide-branding of Clear Channel, it's occasionally worth a listen. But the next DJ that talks in the middle of a song, and about 20 decibels higher than the music currently broadcasted, deserves a death by listening to Michael Bolton and Kenny G on a loud but weak AM station in perpetuity. If I wanted to listen to people interrupt music, I'd play my music in the middle of a court hearing. Shut up and do your job.
I don't abuse my car. People who tell me they have a problem with their car, but have bigger wheels, tires, brakes, modify the suspension, and have wires coming from odd places under the dash, and proceed to tell me that they "don't abuse it". If this is the case, why can't I call them poseurs? Go shut up and die in the corner before making the factory pay for your problem/mistake.
Teenagers that wear pants that sag past their ass but accessorize with a belt anyhow. What better way to tell the world you're a slave to fashion trends?
People that say "BLAM!!!" or "BAM!!!" with a simulated punch every other sentence. Apparently, they're practicing for a drunk wife-beating contest.
People that respond with a muttered bit of disdain when you correct them when they're rather distant from truth, rather than something they heard from a friend of a friend of a guy that knew a gal who got an e-mail and they saw it on TV. Grow up and learn something, you twit.