As a little light science-ish fare for Friday, here's a TED Talk in which David Blaine explains his quest to hold his breath for a really, really long time. He goes through a variety of possible "trick" techniques (none of which worked), and discusses his much-publicized failure to escape from handcuffs during his "Drowned Alive" feat. But then he gets to the interesting stuff -- a seemingly credible story of how he trained to do a sustained breath-hold after breathing pure oxygen. This is a different kind of record than the standard breath-hold, and Blaine did manage to break a Guinness World Record for "static apnea." What makes the story so credible is that other people actually had similar records, and Blaine's static apnea record has since been broken by Tom Sietas (the guy who held the record before Blaine and inspired Blaine's attempt). If only a few guys in the world are working on this record, it seems plausible that Blaine could make it happen.
But while this talk seems credible, it's interesting how we interact with what Blaine says. Can we ever trust him to tell the truth? Probably not: he's a magician, and deception is his M.O. Then again, he could choose to simply tell the truth once in a while. It's impossible for us to know for sure, and that strange balance between "Huh, he seems to be making sense here" versus "Yeah, but he's David Blaine and untrustworthy" makes for a fun twenty-minute video. Have a look, and let me know whether you believe him.
Content note: Part of this video might make you gag. Blaine discusses a "rebreather" made from a "Home Depot" plastic tube, and proceeds to show video of the insertion of this device down his throat; this video may be real or it may be a trick. In any case, you might want to look away during that video clip, as it is truly kind of grim and gross. (This section runs from roughly 4:30 through 4:55. Once he says "So that clearly wasn't gonna work," you're clear to watch again.) I was fine with it, but your mileage may vary.
Note the misdirection (several kinds) near the end.
See also: Wikipedia's account of this feat, which more or less matches up with what Blaine says...but is itself a potentially untrustworthy source. Probably credible: John Tierney's final NYT piece on the breath-holding record.
Disclaimer: DO NOT TRY THIS AT HOME. You may attempt talking kinda goofy mumbly Blaine-style if you wish, but not the breath-holding stuff.