A new version of UDPixel has been released with support for Microsoft Windows Vista. UDPixel is a freeware application that allows you to scan, locate and fix dead or stuck pixels on your LCD screen.

From Wikipedia,

A dead pixel is a defective pixel that remains unlit on an LCD screen. A pixel that stays on a solid color (red, green, or blue) is known as a stuck pixel.

The program needs to be continously run for several hours for best results.

Download from here

(Note: UDPixel requires Microsoft .NET Framework 2.0)