I’m currently composing this post in vim. When I’m done, it’s going to
be posted via the web update form in Mozilla, without using cut and
paste.

This is thanks to what is now my favoritest Mozilla extension yet:
Mozex lets you specify
external applications for viewing source, editing textboxes, mail,
IRC, AIM, FTP, and news, as well as letting you specify a single
universal handler for schemes that Mozilla does not know how to
support. The external applications are called via a context menu,
so you can always get the standard behaviour as well; it also lets
you force the external application on mail:, irc:, telnet:, news:,
and ftp: schemes.

Right now, I’ve configured it to use vim in an xterm for viewing
source and for editing textboxes, xchat for irc links, and an
xterm which connects to a remote host over ssh and starts mutt
for mailto: links. The last one made me go “Oooh” the most.

Mozex is available for Unix (I’m using it in Linux) and Windows,
for recent versions of Mozilla and Firebird.