Y'all are elitist fixie bastards.
I run a computer, though I run it on my handlebars. It would be simple to run one on your stem or top tube, though it would be sideways. Can't be that hard to read. Or if you really want to be cool, get a wireless setup and mount the computer on a wristband so all you have is the goofy thing on the fork and nothing else on the bike.
The one I'm running right now is a cateye (I think) and it uses a rubber band type thing to mount the computer so it comforms to a bunch of different tube sizes and would mount in a lot of places. Be creative and don't let any of these wank3rs tell you what to do. They all suck anyway.