I use Ubuntu for emacs, slime, and ffmpeg.
A feature I'd like to see is an iptables configuration tool from the Administraton menu. The basic panel would support just traffic shaping and perhaps default to giving priority for SSH. This way, if you have a bittorrent application running then any darcs or ssh sessions will still operate smoothly for remote access. You could also add priority for IP phone traffic, or a video game. Preferences could also be pulled in via a txt retrieval from a remote website, so my machine preferences could be saved elsewhere.