No idea if this is the right board so if it is the wrong one then please move it to the right place.

What are pixel buttons and what do they do ?

http://www.google.com/search?hl=en&q...ns&btnG=Search

Pixel buttons are basically just images which are designed to be compact.
The most common forms of pixel buttons are those used for RSS \ ATOM feeds or for replacing the rather ugly W3C validation link images.

The basics idea is to use 1 pixel borders and a small pixel font such as Bitdust2 or Silkscreen.

A pixel button generator.