From Bruce Schneier:

Funniest Joke at the Edinburgh Fringe Festival

Nick Helm won an award for the funniest joke at the Edinburgh Fringe Festival:

Nick Helm: "I needed a password with eight characters so I picked Snow White and the Seven Dwarves."

Note that two other jokes were about security:

Tim Vine: "Crime in multi-storey car parks. That is wrong on so many different levels."
Andrew Lawrence: "I admire these phone hackers. I think they have a lot of patience. I can't even be bothered to check my OWN voicemails."