Thanks for the advice everyone. I actually went to my LBS (actually not the closest one, because I'll drive farther for salespeople who know what they're doing and are friendly) and paid a visit to their resident fixie guy, and now I'm rolling on a 17T Surly fixed cog. It's great. We also got started on an 80s Peugeot project bike, which is my mom's and has been in the attic for more than a decade. This will be my dad's, and he's just about convinced it's time to start riding it to work (2 miles at most). Currently has a SS freewheel, will be fixie eventually. I will post pics.