Screen Lupe is a desktop utility that displays a magnified view of whatever is underneath your mouse cursor. It allows to measure the color of the pixel underneath the mouse pointer and copy it in HTML and other formats to the clipboard. Additionally it has a "move away from mouse" option to be newer in your way.
This is an update for users of the ARTIS Screen Tools package that fixes display problems on Intel Macs. New users should look at xScope from the Iconfactory, the successor of the ARTIS Screen Tools.