Go Kart Plans and Blueprints by SpiderCarts. Seven different plans with detailed schematics on how to build your go kart at home. Including full suspension go karts, racing karts, and free go kart plans.
A rat-cafe-racer? Sounds weird, but the Poland-based Rafal Rodents rat-rod is a stunning bike, and a quick glance at it is more than enough to convince anyone that these guys have their way with custom bike-building.