The default Pinstripe Theme for Mozilla Firebird on OSX is more breathtaking than a hotpocket. On the horizon is Pinstripe for Thunderbird and it looks very promising as well. Some really great work by Kevin Gerich and icon designer Stephen Horlander.
As mentioned on the Pinstripe About page, these are Mac OSX only, since the only way to port this theme to Linux or Windows would involve infringing on Apple's copyrights.
Moron. This theme being OS X-only has *nothing* to do with "infringing on Apple's copyrights." He says it's because he draws them with OS X's Appearance Manager. It would be easy to make a Win32/Linux version of this theme, and it will defintely happen.
Name calling. How productive. From the about page:
The above means that if I were inclined to create a version of Pinstripe for Windows or Linux, I would have to use the regular Mozilla theming method of using slices of images to create an exact copy of the Aqua interface. This would be infringing on Apple's copyrighted work and I have no desire to tangle with their legal department.
Actualy, that was done before. Aqua theme was created for Mozilla (before 1.0) that worked anywhere. However, apparently Apple asked the creator to pull it down, because of copyrights. There are no new versions.
I can only hope he does a gnome theme of some sort (unlikely), or another theme using the regular method.