If you're looking for someone who's obsessive about basically anything, just type it into the search bar and see who pops up.
eharmony has figured out that by asking you a bunch of questions up front, they can then match you with people whose answers are compatible with yours.
Their matching algorithm uses what the website calls a 29 Dimensions Model, which seeks to measure compatibility along things like emotional energy, kindness, character, intellect, humor, spirituality, and more.
Here are the best online dating sites for nerds and geeks, dorks and dweebs, and everyone in between: Who's online: 40,000,000 singles worldwide who send about 3 million messages daily.
How it works: Zoosk opens you up to a wide range of dating options rather than focusing a narrow compatibility niche, so rather than only limited you to matches, you have access to the entire pool.
(Read more about eharmony's compatibility approach here.) Pricing: A three-month membership goes for $57.95/month, but prices go as low as $26.95/month when you sign up for a year.