It's a type of turbocharger. Pretty cool little system, actually.
http://www.aerocharger.com/tech1.htm Unfortunately, it's not a matter of just slapping it on and getting 200HP/240lb-ft. The kit for the Focus won't directly bolt up to the Zetec Contour, but any changes for the Stage 1 system should be somewhat minimal compared to having to run all the crap that a conventional turbo would require.
http://www.aerocharger.com/focus1.htm
