Ever wonder what powers online dating sites like eHarmony, Match.com and PerfectMatch.com. 

When Joe wanted to find love, he turned to science.

Rather than hang out in bars or hope that random dates worked out, the 34-year-old aerospace engineer signed up for eHarmony.com, an online dating service that uses detailed profiles, proprietary matching algorithms and a tightly controlled communications process to help people find their perfect soul mate.

Over a three-month period last fall, Joe found 500 people who appeared to fit his criteria. He initiated contact with 100 of them, corresponded with 50 and dated three before finding the right match. He's now happily in a relationship, and although he was skeptical at first, he says high tech played a big role in his success.

Read more about the technology behind the attraction here.