Just thought I would share a link to a free (for a few hours) bit of software called "PPT Movie" that I have been trying out that converts powerpoint presentations to video.
http://www.giveawayoftheday.com/
or
http://pptexpert.com/index.html
The movie can then be converted (using TCPMP) to the PPC and run as a movie. This reduces the files in size. So instead of running PPT on the PPC in PPT-savy software or as JPEG files you can run it as a movie and pause it when you like using the buttons. Of course you will still need a VGA cable to run it on a projector but it does offer an alternative way of doing it. I know Gigi usually gets a kick out of these sorts of things...