One of my lecturers at university (in information theory) once talked about the conference where he had met Shannon. Shannon was already a legend, and didn't show himself much, so there was a lot of whispering, and someone figured out it would be nice to have him deliver a speech at the dinner. The room was buzzing with anticipation when Shannon got up from his chair; what wisdom would he impart upon the crowd?

“I haven't prepared anything to say. But I could always juggle a bit.” So he took out five balls and showed off his juggling. And that was that :-)

(Interestingly, said lecturer also mentioned this Roman numeral computer; this is the only time I've seen an actual picture of it!)