I personally shoot raw + lowest jpg (whichever your camera allows, if applicable). This is 'coz I often upload pics to friends and it's a wee bit troublesome to open a raw, process it then downsample just so I can pass it to a friend. Moreover, it's very handy for previewing a raw file unless you're using a program with raw browsing capability.
On the other paw, if you have a raw file handy, you can use it to correct minor exposure and color balance issues. It's no substitute for good technique, but it really helps when you absolutely need that gorgeous pic looking perfect.
Then again, unless you're mad about keeping every single shot you take, raw files may not really take that much space. If I shoot 30 frames out there, I may well toss out 28 of them because they're not worth archiving. Not that they're poorly exposed or blur or anything, but that they take up the space that better shots deserve.
