Color Wheel
You can type an RGB triplet in to the RGB value box seperated by commas and select the RGB option to view an RGB color and move the colorspace. The HEX value works the same way, except you use hex numbers, without and leading hash (#) or 0x or anything like that. The top-left square of the colorspace is always the current color show in the box next to the options. You can also click the hash (#) marks in the boxes to select that color and see the values. Browsers that support the TITLE attribute for anchors (IE,Mozilla) will show the hex code if you hold your mouse over the hash mark.

HEX:     RGB:
Darker - Lighter
Increment: Grid Width/Height: x