I've attached a small patch to the manpage that documents the use of SURF_USERAGENT and http_proxy environment variables.
-emg
diff -r 1b312123c34c surf.1 --- a/surf.1 Tue Feb 21 12:00:01 2012 +0100 +++ b/surf.1 Tue Mar 13 11:28:00 2012 -0700 @@ -89,6 +89,13 @@ .TP .B Ctrl\-o show the sourcecode of the current page. +.SH ENVIRONMENT +.TP +.B SURF_USERAGENT +If this variable is set upon startup, surf will use it as the useragent string +.TP +.B http_proxy +If this variable is set and not empty upon startup, surf will use it as the http proxy .SH SEE ALSO .BR dmenu(1), .BR xprop(1),
