The world is changing quickly, and the 'sharing economy' is starting to grow. Soon you won't need to own anything, you will just be able to rent it from someone else who does. Examples of this include AirBNB for housing, or uber for getting around town.
Car sharing is a fast moving niche right now with uber and lyft, but there is another way to make money with your car.
I came across this service called GetAround. They install a box into your car's computer system which allows them to track the vehicle and lock\unlock the doors.
This allows you to rent out the car, hands free, and get paid hourly as other people drive around in your wheels.
The service is only rolled out in a few cities currently, but they are expanding to more quickly.
The idea is a great one, but not without competition. There is another service called Turo which has a similar service, although not as integrated.
Turo is more of a manual process where you actually have to show up and give the keys to the driver. Some people may feel safer actually seeing the person that is going to be driving around in their car, but some people would prefer GetAround where you never have to deal with people. Also if the car gets damaged or scratched there is no way to know which driver caused the problem with getaround. On Turo you could check the car yourself after every rental (or pay someone to do this for you - $$)
Turo's minimum length of a rental is 1 day, wheras you could rent a GetAround enabled vehicle for a few hours.
You could be up and running on Turo today, but with Getaround, you need to pay to have their hardware installed into your car before you can start renting it out.