A Russian programmer has created a brilliant add on for some Canon cameras that use the Digic II processor. It's a tiny program which you copy to your memory card and starts when you switch the camera on. It doesn't affect your camera in any way. This program gives the camera a lot of extra features like a live histogram, battery indicator, possibility to run scripts (which, for instance, can enable exposure bracketing for the A-series) and the most amazing feature: RAW support.

Check it out if you're interested. http://scratchpad.wikia.com/wiki/CHDK Make sure you read the FAQ.