Pixel Color

I've seen a whole bunch of these around, but I can't find one where it's just the pixel color on the form. When I say on the form I mean everything on the form (including web_browser). So how cause I find the color of a specific pixel or the pixel under the mouse (whichever works)? Do I have to do that screen capture and convert it to bitmap and check there? ='( I just want something that's fast and still works, and won't take up too much resources cause im gonn have to going for long periods of time and update really fast.