Want to add a fan in your car

OK so thinking ahead (yeah I know there is still snow on the ground).  This is a nice simple setup for converting a PC fan and an old power adapter (freebee) for a car into a fan for the car.  You can buy fans that do this but they run over $20.  This is a much cheaper solution.  Thought I think I would add a fuse in the design, and a switch just in case.

http://www.instructables.com/id/DIY-Car-Cooling-Fan/