Mis-aligned/badly aimed individual seat lights on airplanes.

Really really dim seat lights on airplanes.

25-watt reading light bulbs in 3-4 star hotel rooms...

And (from a height-challenged person) the miserable 'head rest' on airplane seats. I read somewhere that it's assumed that the flier will want to recline. I find it forces my neck to an uncomfortable position even reclining and it is really really bad sitting upright. Particularly evil if I'm in a seat with an unusually deep (front to back) seat - no lumbar support and a head rest forcing my head unnaturally forward - yikes!

And chewing gum in packets that, once opened, allow all the rest of the gum to fall out too easily.