I'm gonna be unoriginal and say that I would fuck with other people's minds and hopefully creep them out. I love it when they're scared of me. Plus if there's two of me I could get the upper hand in conversations and harass anyone who insults me and ruins my mood.
Yeah, it's not really a smart idea, after all that clone is still you and I doubt it would want to do stuff you don't want to do. I for one would want to be friends with it and hang out with each other.