How many users have you blocked and why?

I have just checked mine and was shocked to see that I have blocked 30...I don't recall blocking that many...however, 10 have been a nasty clone with multiple accounts. Others have been blocked for being unbearably racist or sending me rude emails. Surprisingly, most of mine were blocked when I mostly answered in different categorys, none on polls and surveys. How many are on your blocked list and why?