Hoople - 9:14 pm on Oct 12, 2011 (gmt 0)
If your machine has Wine on it you can run MS-Windows format Firefox binaries from Portable Apps. Lots of other apps choices there too. 'Wine Tricks' allows you to load Internet Explorer 6 and Internet Explorer 7 on some Unixs.
Side benefit is you'll get those other browsers needed for thorough site testing.