Canon 20D & RAW

Here’s a long thread which has almost convinced me that I should shoot RAW this weekend.
If I wanted to batch process I can probably do something like this:
for i in *.cr2
dcraw -c $i | ppmtojpeg > `basename $i .cr2`.jpg

RAW files are known to be much bigger. File sizes?
$ du -csh *
6.7M img_5881.cr2
24M img_5881.ppm
31M total

$ du -csh img_5879.jpg
4.0M img_5879.jpg
4.0M total

Shooting in RAW costs me almost 3MB of space per photo. I’m game to try it but the advantages will have to be absolutely amazing if I’m going to use it!