The only advice i can offer is to make sure that you tailor your examples to your audience. CD, MP3, and DVD collections are fun topics and should keep your audience's attention. I would stay away from port scanners and packet sniffers, though. ;)

jeffa

L-LL-L--L-LL-L--L-LL-L--
-R--R-RR-R--R-RR-R--R-RR
B--B--B--B--B--B--B--B--
H---H---H---H---H---H---
(the triplet paradiddle with high-hat)