I discovered a handy little tool called ‘Pixie’ last week which can display colour values for any object on a Web page, a window of an application or on your desktop. Download and just point your mouse cursor to a solid or text color. Pixie then displays the colour values in several formats including the html colour code, hex and rgb at the exact pixel you point your mouse at. The X and Y coordinates are displayed as you move.
Its only 12kb as well.
One thing to be wary of is the various hues of text, so as you run over what you think is a solid colour it changes as you hit the edge. Someone tells me this is anti-aliasing (must look this up). There is a hot key (ctr + alt + z) that can magnify a 32 X 32 pixel area showing exactly the pixel you are looking at.