I have been having some fun lately.
One way to hear the fun is to
cat /usr/share/icons/*/* > /dev/dsp
which lets you "listen" to your tiny little icon files!
More fun was a little prank I pulled on my co-worker.
I have a server that sits next to my co-worker's desk. I installed the 'beep' program on the server and from the ssh across the room had a great time watching him get more and more worried/confused at the random beeping that he couldn't find.
Just thought I'd share that.