rude people
How do I loathe rude people? let me count the ways.... cutting you off in line, not watching where they're going, improper lane shifts, leaving their shopping cart in the middle of the aisle...

lab work
Peeing in cups, sticking things up your nose and drawing blood. What's there not to hate.

Irrational People
"You know what? I wish we could have the ENTIRE summer off!"- 29 year old co-worker

People who can't/don't/won't control their kids
"jimmy! you stop that! stop that right now! I mean it!"

or

"damn kid was right here... oh, there he is, hanging from the rafters!"