This place makes racing tricycles, lathes custom hubs, custom cartridge bearing freehub bodies, custom conversion kit for turning road bikes into road trikes. Wildly cool stuff. Check out the galleries.

http://myweb.tiscali.co.uk/trykit/page%201.htm

Custom cartridge bearing adjustable cup! Not sure what the point of that is, except that you could choose axle length independently.

Bike to trike conversion axle setup. Disc brake no less! Single center pull cable, two brakes?