I was doing my usual browsing and I stumbled on the following:
http://www.automotivedesign.eu.com/articles/43866/Torotrak%20V-Charge.jpg
It’s called the Torotrak V-Charge. It is basically a variable drive supercharger setup (tests configs are using a Rotrex blower). The setup is supposed to provide a good bump in torque down low while keeping the mid to top end performance that centripetal blowers are known for. It is gearless so it operates silently.
More info…
http://www.torotrak.com/pdfs/pr/2012/TOR7544%20V-Charge%20Test%20Success.pdf
http://www.torotrak.com/content/464/V-Charge-Variable-Drive-Supercharging-Exploded-Assembly.aspx
http://www.torotrak.com/content/459/V-Charge-Test-Drive.aspx