Jeopardy host Alex Trebek arrived at the National Geographic World Championship, which he was hosting, on crutches today. Apparently he fell while "chasing a burglar" at 2:30 am at his San Francisco hotel and snapped his Achilles tendon. Hm. I'll take improbable explanations for $800. Also, what is: ouch. Jeopardy jokes! [ABC 7, photo via Getty]