you know, Timberland made a "fixie" shoe so to speak, called the Folsom. Kinda ugly I think, but it does have a "3/4-length forefoot monoflex bike plate" which I assume is a shank. There out of production, but I'm sure someone is selling them online. Here's Bikesnob's write up about them:
http://bikesnobnyc.blogspot.com/2009...g-rituals.html