Oh so have I, and I'm specifically excluding the "nah nah nah nah boo boo" folks. The only thing those people do is encourage me to pay no attention to them. I was really talking about those that are able to just go live life, have a great time, and somehow seem to serve as a shining beacon for those lost at sea! It's even better when they have a sense of humor as well as passion. (Writing "most of them" on a landing card that has insufficient space is as creative as it is hilarious!)

What specifically does your friend do to piss you off?

He can be belligerent and totally unsympathetic to most people in any sort of customer or human facing role. He's a better tipper now than he used to be, but can still be rude to harried waitstaff (i.e., when it's clear they have a lot of customers to handle he would get annoyed at having to wait for a refill). He dislikes companies/businesses charging him more than he thinks things are worth, while simultaneously being one of the strongest free-market capitalist supporters in my social circle. And he'll let their employees know he's upset. The irony is apparently lost on him.

With the TSA he likes to derail the process (unless he's short on time). Not just asking for a pat down rather than the scanner (if I gave myself more time at the airport I'd likely do the same), but to the point of abusing the worker rather than making the system itself slow down. Also, he has little regard for those behind him in line, and doesn't mind delaying them a few minutes so he can feel better about himself.

As I haven't spent much time with him (physically parted ways after college) the past few years I can't really recall any more specific incidents, but it was a reason that, in college, it took us about 6 months to become friends. I thought he was a jerk, and I was right, he just happens to be a good friend as well.