If you are adventurous/daft/publicspirited enough you can give Firefox 2 alpha a try.
http://www.theregister.co.uk/2006/03...refox_2_alpha/
NB THIS IS SERIOUSLY ALPHA SOFTWARE. IT WILL BREAK. IT MAY NOT WORK AS EXPECTED. USE AT YOUR OWN RISK!!!!
But then to say you helped in development gives a certain kudos.