1)   Pixel Ruler 3.10
Pixel Ruler features horizontal and vertical orientation, dynamic mouse measurement tracking in pixels, cool design.

 2)   JR Screen Ruler Pro 3.0
The JR Screen Ruler is a great tool that allows you to accurately measure anything on your screen. This is especially useful when measuring graphics, web page browser sizes or whatever. Screen Ruler can display Pixels, Inches, Picas, Centimeters.

 3)   JR Screen Ruler 1.4
The JR Screen Ruler is a great tool that allows you to accurately measure anything on your screen. This is especially useful when measuring graphics, web page browser sizes or whatever. Screen Ruler can display Pixels, Inches, Picas, Centimeters.