To find the love of their lives, many people have to gloss over incompatibilities, such as differing senses of humor or lack of communication during bank heists. Seek a soulmate while retaining your standards with today's Groupon: for $60, you get a three-month trial membership from eHarmony or Compatible Partners (a $110.85 value).

Founder Dr. Neil Clark Warren studied the key ingredients of successful marriages to produce the 29 Dimensions of Compatibility model. A pair of websites—eHarmony and Compatible Partners, eHarmony's gay and lesbian site—plug canoodling candidates into the advanced cupidean theorem, which is then solved until x equals lifelong-love likelihood. Fling flings aside in favor of enduring enchantment as the eHarmony method deeply analyzes traits such as adaptability, self-concept, emotion management, and taco-shell preference. They'll use their findings to determine the most likely life-loves out of more than 33 million users who vary in religious background, race, age, and location. Along with a list of matches, your membership grants you access to a safe, anonymous communication system, as well as guidance on ice-breaking from outgoing penguins.

For prospective daters in need of tips and tricks, the relationship experts at eHarmony have produced an encyclopedic library of relationship advice articles, and the match-masters at Compatible Partners have posted success stories of smitten someones who have embraced their guidance. A 2009 Harris Interactive study conducted for eHarmony suggests that over an 18-month period, eHarmony accounted for nearly 5% of new U.S. marriages, more than 1 million monogamous, unmarried relationships, and nearly half of all smoldering smooches in the rain.

Reviews

A number of press outlets, such as Time and the Huffington Post, have featured eHarmony. Business Insider named it one of the World’s 100 Most Valuable Startups.