Meazure is a program that measures, magnifies and captures the screen by providing a battery of features in a cohesive user interface. Even better, Meazure is <img src=/S/free.gif border=0 alt=free width=30 height=15>! Features include:

Measure objects on the screen such as images, windows and icons
Capture arbitrary portions of the screen
Magnify the screen up to 32X magnification
Read the color of a screen pixel in RGB, hex RGB, CMY, CMYK, HSL, YCbCr, YIQ
Display rulers anywhere on the screen
Display a grid overlay on the screen with adjustable grid spacing
Measure using a number of units including pixels, points, twips, centimeters, or user-defined
Record measurements to an XML file for later playback or external processing
Calibrate screen resolution to provide accurate measurements
Save and restore measurement tool positions using Profiles
Use predefined Profiles for common screen and video sizes such as NTSC and PAL
Configure the user interface to show only the information you need
Many more features. See the detailed context-sensitive help