My uncle, Greg Nichols designed and built the original Hydroski in the late 80s. The odd looking hull is what was really innovative about the boat. Those rectangular channels actually filled with a little bit of air and the entire thing would get on plane and haul! Even with a weak sauce 440 cauna it would get up near 50 mph. Some were also sold as "kits" where you could install all of the running gear from your Kawasaki 550 and with no other changes you gained a ton of top speed. I was at an endurance race in the late 80s from Ensenada out to some island and back, and the top speed on the hydroskis was so unfair compared to the 550s it wasn't even funny. The Hydroski was also all handlaid FG, and they are way stronger and lighter than most other stand ups. In the early to mid 90s the Hydroski had a brief revival as the Nichols Watercraft Typhoon with some minor but significant changes. The front pontoons were widened a little bit, the stand up tray side walls were thinned to enable a broader standing position, the air intake was moved to the handlepull, and they were 100% carbon fiber. Nichols watercraft took the hydro hull design to the max with the sit down trident in the early 90s also. For my birthday last year my father and uncle found 3 old hydroskis that hadn't run in a long time and fixed one up for me, brought back some great memories. For a little while we even had a proprietary 800cc v4 two-stoke that was used in the Trident. That engine was developed after we had repeated supply problems.
I was fortunate enough to work as a Nichols Watercraft factory Test Rider in highschool along with... get this... Jimmie Johnson (of Nascar fame), back then he was a Junior in Highschool and already the youngest winner ever of Mickey Thompsons Off Road Challenge (I think he won that when he was 15). There's a bunch of pics in my photobucket of both the Trident and the Hydroski.
http://photobucket.com/nicholswatercraft
If you have any other questions feel free to shoot me an email.