"I never thought I'd be back here, and I am because of so many of you in this academy," said Affleck, who shared a screenplay Oscar with pal Matt Damon 15 years earlier for their breakout film "Good Will Hunting."
Among the wisdom he's acquired since then: "You can't hold grudges — it's hard but you can't hold grudges."
Lee, who previously won best director in 2006 for "Brokeback Mountain" (which also didn't win best picture), was typically low-key and self-deprecating in victory. His "Life of Pi" is a fable set in glorious 3-D, but Spielberg looked like the favorite for "Lincoln." The film also won for its cinematography, original score and visual effects.
"Thank you, movie god," the Taiwanese director said on stage. Later, he thanked his agents and said: "I have to do that," with a little shrug and a smile.
"Les Miserables" also won for sound mixing and makeup and hairstyling. The other Oscar for "Django Unchained" came for Tarantino's original screenplay. Asked about his international appeal backstage, Tarantino was enthusiastic as usual in saying: "I'm an American, and a filmmaker, but I make movies for the planet Earth."
Speaking of global hits, the James Bond action thriller "Skyfall" won for its original song by the unstoppable Adele (with Paul Epworth). It also tied for sound editing with "Zero Dark Thirty," the only win of the night for Kathryn Bigelow's detailed saga about the hunt for Osama bin Laden.
Among the other winners, "Searching for Sugar Man," about a forgotten musician's rediscovery, took the prize for best documentary feature. Pixar's fairy tale "Brave" won best animated feature.