Comment by mortenjorck

If this isn't the smoking gun, it's at least the smoke:

  Unlike other locating tags, there is no battery in the iFind tag. 
  It recycles electromagnetic energy and stores it in a unique power bank.

This is the sort of language that never describes an actual technological breakthrough. It's a combination of a description that's too pat, too abstracted, with a feat that is too impressive to go without at least some reference to the actual processes that make it work.