I have two alts on Facebook. One of them is so I can keep my online friends and real-life friends separate. But the other was for The Sims but I ended up putting those two accounts in a relationship. So I guess I'm narcissistic
I was planning on closing both of those down at some point though, and just using my personal one.
I also have an alt on Twitter, which I use for when I stream on Twitch and for other gaming stuff. I'm going to keep this one most likely.
I have personal accounts on both though.