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.
Internet dating sites are the love machines of the web, and they're big business. eHarmony and similar sites drew 22.1 million unique visitors during just one month, December 2008, according to comScore Media Metrix.
And unlike many social networking sites, they actually make money - the top sites bring in hundreds of millions per year, mostly in subscription fees.
These online dating services run on a curious mix of technology, science (some say pseudoscience), alchemy and marketing. Under the covers, they combine large databases with business intelligence, psychological profiling, matching algorithms and a variety of communications technologies (is your online avatar ready for a little virtual dating?) to match up lonely singles -- and to convert one-time visitors into paying monthly subscribers.
All is not chocolates and roses online, however. Security is one big challenge for e-dating services, which can attract pedophiles, sexual predators, scammers, spammers and plain old liars - most notably, people who say they're single when in fact they're married.
And sticky questions have yet to be answered over what rights such sites have to your personal information - how they use it to market other services to you, if and how they share it with advertisers, and how long they store it after you've moved on.
Finally, there's the biggest question of all - do these tech-driven, algorithm-heavy sites work any better to help people find true love than the local bar, church group or chance encounter in the street?
Armed with these questions, a passably decent head shot, and a very patient wife, I set out to discover what's under the covers in the world of online dating.
The business model behind online dating
A well-oiled Internet dating machine can generate well in excess of $200 million (£140m) a year in a market that's expected to top $1.049 billion (£740 million) in 2009 - only gaming and digital music sites generate higher revenues - and is expected to grow at a rate of 10% annually, according to Forrester Research .
Most online dating sites generate the bulk of that revenue from subscriptions, although free, advertising-supported sites are starting to gain some ground.
Most dating sites allow users to sign up and create a profile for free.
Before communicating with matches, however, visitors must sign on as a paying member.