Recently found a very nice project. Called Firefox Builder The service is intended to create Firefox and Thunderbird assemblies customized for your interests. The choice of versions of Firefox on the basis of which you can make your builds is limited to versions from 3.0.10 to 3.6 a1pre, and Thunderbird from 2.0.0.21 to 3.1 a1. Addons and themes can be added to builds. They can be selected from the catalog or downloaded by yourself.
This is how the process of creating the browser HabraLis looks like the picture is a link to build HabraLis ')
Additions
The site could not stand the Habroeffect and is currently moving, by the evening promised to earn.