rxvt url

==> To enable url-select place the following in ~/.Xdefaults
==> (change to whatever suits your needs)
==> URxvt.perl-ext-common:  default,url-select
==> URxvt.keysym.M-u:       perl:url-select:select_next
==> URxvt.urlLauncher:      firefox
==> URxvt.underlineURLs:    true