I've never been the best man at a wedding. I was a groomsman once (for a good friend) and an usher (for my sister).

Pro tip: if you agree to be a groomsman (or bridesmaid, I guess), in any capacity, don't back out for bullshit reasons less than two weeks before the wedding. Especially if the bride just dropped $300+ on fancy programs with your name in them.

I haven't spoken to that guy in 12 years next month.