Mozilla/5.0 (OS/2; U; Warp 4.5; en-US; rv:188.8.131.52) Gecko/20060729 Firefox/184.108.40.206 Often, files are served with different extensions then they should normally have, depending on the MIME-type specified in the HTTP header, or no extensions at all. Examples: - http://rsw.beck.de/rsw/shop/default.asp (Content-Type: text/html) Firefox wants to save as "default.asp" whereas for the user it would be much more useful if it would be saved as "default.html". (SeaMonkey does it better, and offers to save as "default.asp.html"). - http://front.math.ucdavis.edu/math.AP/0101001 click on the PS icon (leftmost icon just above the title line) (Content-Type: application/postscript, Content-Encoding: gzip) Gets saved as "0101001.gz" whereas it would be better to save it as "0101001.ps.gz". - http://arxiv.org/ps/astro-ph/0601250 (Content-Type: application/postscript, Content-Encoding: gzip) This gets saved without any file extension, saving as 0601250.ps.gz would be better. - http://arxiv.org/pdf/astro-ph/0601250 (Content-Type: application/pdf) This gets saved without any file extension, too. Saving as 0601250.pdf would be better. Not all users might want this file extension rewriting, so this should probably be an option.