Instructables user mrfixits writes:

This Tesla Tornado is made using a Subaru blower fan motor, complete with its 3-position speed switch mounted on the base. The blower motor has a flywheel fabricated out of Lexan with 6 neodymium magnets mounted in it. It magnetically couples with 6 magnets in the Tesla Pump disc pack, which is inside the vortex tube. The Tesla pump discs are magnetically driven by the blower motor flywheel magnets, so there is no direct connection. The pump disc pack is self-centering, and there is no rotating shaft, shaft bearings, or seals required.

Because nothing says xmas like the slurp of that water pump! Great walkthrough of the building of this Tesla Tornado.