Not sure how small the self-contained DV cameras will go...smallest I've had my hands on is the older "4000" version of
this one which, with some "creative" disassembly, you might be able to fit on an RC car.
In terms of miniaturisation, you're probably best to go with the mini wireless cam. What kind of video outputs does the reciever support? As far as I have seen, all the USB boxes and the Avermedia PCMCIA card will take RF (Antenna), Composite/RCA and S-Video inputs; so there's plenty of connectivity
