I had to get stuck in to some re-styling of a gridview today and found myself constantly firing up Fireworks and using the Color Palette to tweak the shade and get the hex code (yuck!), after using Colorzilla to extract it from the page i was working on.
After half an hour of tediousness i found something pretty much straight away via Google (and its free)...
ColorPic from Iconico.com
Nice and easy to use and speeds up the job, hope you find it as useful as i did...
Taken from my personal blog