Thanks for replies. But if i understood well I don't need hardware support of USB as i mentoined. I can use V-USB in every (almost) atmega chip. I was thinking about using that dedicated USB pins. I would like to know more about that.
I'm going to make some vehicle based on R/C car. But still thinking what would be the best solution. For communication (webcam stream) i will use regular WiFi connection. MikroTik board connected to seagate dockstar (picture bello). ZigBee could be more simple and cheaper. But dockstar is armel based computer and it is more poreful than Arduino. So Arduino will be just for controling servos and I/O sensors.