Here's a site that lets you upload a photo of yourself, which it then compares mathematically to a bunch of celebrities in order to guess who most resembles you. Here's what it thinks about me:
I have no idea who half these "celebrities" are. Try it on your own photo. The site lets you upload any photo for free without registration, so there's no need to fiddle with passwords or risk getting yourself spammed. It's pretty quick too.
Another (free) service will tell you which parent (mom or dad) your child most resembles. I'm going to upload a photo of our mailman just to double-check.