Now that this thread exists I really notice when I do something "weird" now. Never gave it much thought before.
I hate shaking hands. I will think up any excuse I can to avoid it. I'm not one of those people who freak out about germs and such, but for some odd reason I just think it's super nasty to touch someone's hand. It also doesn't help that this feeling keep getting validated by people I know. A friend of mine works at a bank and, after shaking hands with a client, he saw there was blood on his palm. Yuuuuuuck!
Oh man, social awkwardness... Yeah, that's a tough one to overcome since you constantly have to go outside your comfort zone and be able to put it behind you if you do accidentally say something silly.
I was forced to get through it for my job. There's a lot of talking on the phone and I'll admit I inwardly panicked every time that damn thing rang and I had to answer it. Then again, not being able to see the person really helped and I've noticed that little practice I get at work has helped me when I'm face to face with someone.