I have one, and I like it.
My dad has two - one that he uses all the time, and a "secret" middle name. He wouldn't tell anyone his secret middle name - even his kids. I went crazy for years guessing how bad it could be - was it a girl's name, a dirty word, etc? I finally found it out when we had a surprise 50th birthday party for him and my mom pulled his baby book out, which had his full name written in it. It wasn't that bad, I don't know why he keeps it a secret! Apparently my uncle has a "secret" middle name too - I don't know what it is, but it might be the same as my dad.