Yes, I have read much of this book and seen several articles/videos on road privatization. This thread is for people posting their out of the box ideas.
Here are a few of mine:
The simplest would be highways. These already exist, but could be improved upon by Bitcoin. The road I used to commute to work on had tolls, but you would buy a pass with an RFID in it and instead of stopping at the toll booth you just drive through a side lane that recorded your RFID as you passed through. For the card I would just go online and fill my account with money, I set it up to auto-draft when it got below $50.
There could be a few options of doing this with Bitcoin. Either have an account the same way with the option of funding it with Bitcoin anonymously, this would prevent any sort of way to track people's movements. Another option is having a tiny Bitcoin device that holds your bitcoins which can actually transmit a transaction at the tolls for payment.
Another option is to have a lane that is a smart road. Cars could be upgraded to be able to work on the smart lane where magnets or other devices are embedded into the outsides of the road and the car detects them, keeping a safe distance inside the lane and keeping a safe distance from the car ahead and behind. This would allow a faster commute and the ability to not have to pay full attention to the road while on the smart lane.
Smart roads also allow for the ability to charge electric cars via electric induction with a two way communication which could allow for payment via Bitcoin easily in real time using microtransactions. It would also allow for Internet communication from the road allowing people to surf the Internet and check their e-mail on their way to work or wherever they are going.
Smart roads would also eliminate the problems of drunk driving or worrying about people talking on their cell phones. And with car accidents being one of the main causes of death and drastically reducing auto accidents would cut car insurance drastically and would make up for the cost of upgrading to pay for the better road.
Highways and long distances are the easy part. The tricky part is in towns.
One obvious one is the local merchants paying for it which has been mentioned. Disney World actually has their own private roads near their parks.
For payments at roads with stop lights I had the idea that people could pay for faster light changes where the price to time would exponentially increase depending on how much quicker you would want the light to change. And it would accumulate depending upon the amount of people sending their money to get it to change. So when you are sitting in traffic pissed at the amount of time it is taking and you are in a long line of people you can just hit the amount of BTC you want to pay to speed up the light and if there is a long enough line then you can all speed it up. It would of course have a minimum amount of time to allow two way traffic. If you had a big night or an emergency you may be willing to spend a buttload on having a clear shot to your destination. Though with smart roads, if all cars are moved by the road there would no longer be a need for traffic lights and traffic would be moved at the most optimal pace possible.
For roads in front of homes I would love to own those roads and provide free use of those roads. We could get rid of all of the electric poles, telecom poles, etc. I would create the road with large cement pipes which would allow piping electric lines, telecom lines, water pipes, sewer pipes, gas pipes, heat pipes, etc. This could also allow for multiple companies renting space and provide more competition between utility companies.
Another option for these thousands of miles of road/surface area facing the sky is solar. Either panels above roads or work on a polymer that could be used on the road to produce electricity.