5. Henry Miller, Anaïs Nin, and June Miller

Henry Miller was no stranger to sex, as anyone who's read, well, virtually any of his work can attest. But he might have met his match in pioneering female eroticist Anaïs Nin. Nin was entranced by Miller, and so bankrolled his time in Paris and the first pressing of Tropic of Cancer. They also had a lot of sex. Then Nin became somewhat... infatuated with Miller's wife, June, entering into a close and sexually-charged friendship with her. Nin lavished June with jewelry, money, and clothes, often to the point of bankrupting herself, but the pair never actually consummated anything — Nin simply considered June the perfect femme fatale. Nin's diary documenting the trio's exploits was eventually turned into a not-too-terrible film called Henry & June, which is a fun way to feel kind of smart while watching what is essentially softcore porn starring famous literary figures. — Alex Heigl

4. George Harrison, Patti Boyd, and Eric Clapton

The achingly pretty Patti Boyd had already inspired "Something" and a few other George Harrison songs by the time the couple's friend Eric Clapton developed a bit of a thing for her. Clapton's solution was to begin dating (and living with) Boyd's seventeen-year-old sister, Paula. Oh, and to write "Layla," one of the most searing proclamations of unrequited love ever put to tape. Harrison and Boyd separated in 1974, and she married Clapton in 1979, before leaving him in 1984 and divorcing him in 1988. (Apparently there was quite a line at the courthouse.) Harrison and Clapton, for their part, remained good friends and kept a great attitude about the whole thing, apparently even referring to themselves as each other's "husband-in-law." Hey, it sure beats "weiner cousins." — A.H.

3. Petter Lindström, Ingrid Bergman, and Roberto Rosselini

You might have inspired a slew of passive-aggressive Facebook status updates when you broke up Brendan and Julia, but you probably weren't ever publicly denounced in Congress. Ingrid Bergman moved to America while still married to neurosurgeon Pia Petter Lindström, but while filming Stromboli in 1950 with Roberto Rossellini, the two fell in love and conceived a child, the gloriously-named Renato Roberto Ranaldo Giusto Giuseppe Rossellini, or "Robin" for short. When the news broke in the States, Bergman was savaged: Senator Edwin C. Johnson called her a “free-love cultist,” and "a horrible example of womanhood," and "a powerful influence for evil," in characteristically subdued Congressional language. Oh, and then Stromboli bombed. Ah, well. At least we got Isabella Rossellini out of the whole thing. — A.H.

2. Prince Charles, Camilla Parker Bowles, and Princess Diana

Kate Middleton and Prince William may be Cinderella and Prince Charming incarnate, but the royal romance between Prince Charles and Princess Diana was more Grimm than Disney. Their marriage was marred by an affair with Camilla Parker Bowles, who Charles met at a polo match during the ‘70s, which we’re pretty sure makes this the most British love story ever. Diana called Camilla "the Rottweiler;" Camilla’s husband, meanwhile, not only knew of the affair but was polite enough to consent to it, which definitely makes this the most British love story ever. The Prince and the Duchess eventually got their happy ending when they wed in 2005, but that was only after they'd both divorced their partners and Diana died tragically in a car accident, which kind of puts a damper on their whole "inspiring, decade-spanning romance" thing. — J.P.

1. John F. Kennedy, Marilyn Monroe, and Jackie Kennedy

What can we say about this love triangle that hasn't been said? It'll probably be remembered in mythic terms long after slightly more consequential affairs like the Cuban Missile Crisis are forgotten. Still, it's hard to watch Monroe's notorious "Happy Birthday, Mr. President" performance and not think, "Cuban what who?"  — Peter Smith

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