On OKCupid.com, a free dating site with women who know how to post photos that they didn't take themselves while making kissy faces in the mirror, there is a matching system.  Based on your interests, your attributes/skills (cause women like a guy with skills), how you answer questions and where Venus is in the sky, you are considered a percentage match to the other person.  This comes in the form of % Match,  % Enemy and % Friend.  Recently I got an email with the title "Anti-Match."  Read for yourself:
"According to OKCupid we are a 0% match. I think that's awesome."
I disagreed:
"I know you like laughter, but I hate it.  You're a teacher, but I think education is stupid.  You have a huge crush on Harry Potter, however, and I used to as well, so I'd say we're more like an 11.7% match.  Not 12%, cause I hate rounding.  Which also cost us those three-tenths of a percentage match points."