Meazure - screen ruler

Meazure, a jaw dropping ruler. It is free and open source.
Download: http://www.cthing.com/Meazure.asp
Source code: https://bitbucket.org/cthing/meazure

Meazure's features (copied from the website):
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

PS. I use "Linijka 1.0" on regular basis (portable by itself).This ruler is easy to use with dozen of features: vertical/horizontal, multiple instances, colors, double sided ruler, fonts. Unfortunately only polish language is available. About 3 years ago I asked the author through email about translating to english, he was very keen but nothing has happened since then.
http://www.e-programy.pl/pliki/d8d480b7310d7490f9236d058613dea5.zip