We don't care about the privacy of street signs do we? How about implanting RF tags in street signs to help you navigate around?

Street Smarts (http://www.newscientist.com/blog/technology/2007/05/smarter-streets.html)

This is similar to how the roads in the Mars (red, green, blue) worked. A transponder marked off the roads for your autonomous vehicle to follow. Oh how I'd love to have an autonomous vehicle. Dr. Pickle? Are you still working on those? (Yes, there is a real Dr. Pickle and he was an engineering professor when I was in college but went to work for someone else later on.)