What are some of the names of the rental car companies that rent cars by the hour in big cities.?

They are not the traditional rental car companies. They require a sign up fee, and then you can rent cars all year long and pay a small hourly rate. I need one in Chicago.What are some of the names of the rental car companies that rent cars by the hour in big cities.?
I've never heard of a company that rents cars by the hourWhat are some of the names of the rental car companies that rent cars by the hour in big cities.?
Why not just take a taxi cab? No sign up fees, and you just tell the driver where you want to go.