Cited as a reference
Exposed ? Free Energy Magnet Motor
Why people recommend it
Cited when free energy or permanent magnet motor claims come up, to show how such demonstrations are faked with hidden batteries and switches.
Watch for: Shows the trick, not a working device
In their words
See here for one example of how to trick people into thinking they work:
Eric on electronics.stackexchange.com, Oct 2014. CC BY-SA.