Mine is (hold onto your chair tightly now) NeoFelis.
I use that and one other one (that one's for shopping, usually) primarily. Sometimes I have to add numbers on the end, of course. I'd rather have to come up with a ton of passwords than put in a username I'm going to forget.
I've yet to turn down a Friend request on the official site yet. Even from a couple people who had their entire pages hidden. I was on their forum for a bit, but it's just too much for me to deal with, and after the recent problems with the Exchange, I just check my page for messages or see how something I've uploaded is doing.
Night!/Morning! I've got an appointment to check out a rabbithole of sorts (a.k.a. sleep and dreaming) and mustn't be any later than I am!