Here's the table I use when choosing HTML colors. It's SO helpful, and it's made from the RRGGBB color hexes, so they're almost certain to work on all browsers/computers.
http://www.december.com/html/spec/colorchips.htmlAlso, here is a color selector I use for those of you who don't have nifty Photoshop. This allows you to get the hex code for any color on your screen, in any hex (hex, delphi hex, VB hex, rgb, hsb, and most importantly, HTML!)
http://instant-eyedropper.com/?ref=ie