also, the Wikipedia "Wave Power" page has a reference to the original 1976 patent for the Duck credited to just Stephen Salter.

As Jack said: "I would like to see Don provide more subsatantive documentation of his claims"

You've been very negative in this thread without providing even one link to something that discredits the Duck. So how about it? Can you actually point us to some credible evidence that this is snakeoil?

While you are away looking, here are some other articles to keep the others amused while they wait (and wait, and wait...)

Science News article "Oceans of Electricity"
"Stephen Salter of the University of Edinburgh and other researchers, mainly in the United Kingdom, devoted about a decade to the goal of building large-scale, 2,000-megawatt wave-energy plants. The collapse of that program--whether because of inadequate support or overly ambitious goals--left wave energy with a credibility problem and scared off investors. Now, wave energy is riding a new surge."

a little page at TechnologyStudent.com with cute animated GIFS of the Duck

Australia's Research Institute for Sustainable Power's page on wave power:
"The Salter Duck is able to produce energy extremely efficiently, however its development was stalled during the 1980s due to a miscalculation in the cost of energy production by a factor of 10 and it has only been in recent years when the technology was reassessed and the error identified."

This article from Glasgow's Strathclyde University  actually criticises the Duck (i'm trying to help you out here, Don):
"Due to the complicated design it is expected that it will take more years of development and is reckoned to be a `next generation' device." (Next generation, eh?  Obviously years ahead of it's time!)

[The US DoE's "Energy Efficiency and Renewable Energy"s web page on wave power] says:
"Sophisticated mechanisms--like the Salter Duck--use the bobbing motion of the waves to power a pump that creates electricity." (hmmmm.  Sophisticated snakeoil!)

Now, American institutions are much more capable of passing snakeoil, so this October 2005 White Paper from MIT is probably less believable :) (pdf warning).  Here's a more complex quote:
"One of the earliest innovations is the design by Professor Stephen Salter of the U. of Edinburgh. It consists of a long line of two-dimensional cams hinged on a horizontal axis near the sea surface and parallel to the shore. The cross-section resembles a tear-drop with a pointed beak facing the sea and a circular rear facing the shore. The diameter is large enough so that little energy is transmitted past the cams. Energy is extracted from the rolling motion of the cam. By adjusting the energy absorption rate optimally, the cam radiates waves that are equal in ampliutde but opposite in phase with the waves reflected by the mere presence of the cam. Hence all the incident wave energy can in principle be removed. There are two criteria for complete (ideal) absorption: (i) the cam motion must be resonated by the incident waves, and (ii) the power extraction rate must be equal to the rate of radiation damping carried by the radiated waves due to the cam motion. Because of its geometry, the device is widely known as Salter's Duck."

Oh, and here's the Wave Power Group's official homepage at Edinburgh University (one of the UK's oldest Universities with a great tradition in snakeoil!)

It's 3am here now, so I better get to bed. I'll check back in the morning to see what you have come up with.

I have trouble just reading all of the comments. I think it is important to keep all crucial components of the argument withn the comments and provide links for support. I don't think it is fair to say someone else has to read 10 linked documents before they are allowed to respond to a comment.