I recently read about a Swedish company called Coming Through, which retrofits Honda Goldwing motorcycles to be "tow trucks." After all, they can get through traffic and are beefly enough to haul most passenger cars. Rather than starting with a tow truck (of the more traditional style) and engineering it down, I am sure they started from the need and build a solution from there. The design is cool and I could see cities having whole fleets of these to deal real-time with stalled cars on freeways that gunk up morning commutes.