I'm the owner of a Canon Powershot SX10IS and I've heard about CHDK a long time ago. After checking the firmware with ver.req on the root of the SD card, I understood it is running under 1.03A.
Today, I decided to give it a try, on a 4Gb SDHC card. I extracted the files from the downloaded file (sx10-103a-0.9.9-1418-full.zip), as suggested and was able to find the 'Firm. update' option on the Settings menu under Playback mode.
I ran it and I could see the CHDK logo and a blinking blue light, giving the impression that the camera was being rebooted.
Maybe it is stupid of me, but now I don't know if the CHDK is actually running (Menu button still brings me to CANON settings menu) or how to find it.
Thanks in advance for all your help.