Since there's been so much goofy hype about foiling monohulls on these pages, I thought it only propoer to drop a few photos and a link to the Rinspeed Splash foiler out of Switzerland circa 2004.
http://www.rinspeed.com/pages/content/frames_e.htm
I couldn't find any price for the vehicle, but after looking around on the pages at their site, it's clear it wouldn't be cheap. It will get you babes and it will get you a choice parking spot at any Metrosexual club in North America.
The People's Foiler concept gone to its logical, ridiculously expensive conclusion. And no, much to Doug's chagrin, I don't believe it's a Moth derivative, though it is capable of 80 KMH (43 knots) on the water in the foiling mode.
Have fun at the Rinspeed site. They have some wild stuff there.
Chris Ostlind