I was once at a Microsoft conference when a speaker didn't show. We waited 15 minutes when finally a sweaty, scruffy dude comes running into the room panting all apologetic-like. Apparently he had been in his boxers relaxing in his hotel room about a mile away and 15 minutes prior when he got a call from the organizers. His presentation wasn't in 2 hours like he'd expected. It was right then and there. I felt really bad for him.