Harm says:
The favicon of this wonderful site has a white background (see http://tweakers.net/ext/f/1yTIo8mj3KD7xi2dTK9zl9Lg/full.png for a small screenshot). This is not a problem in many current browsers, but for Firefox 3 it is. Could you please fix this?

See also http://robert.accettura.com/archives/2008/03/22/webmasters-make-your-favicon-transparent/ for more information about this request.