Andy - re. Milk Stout: I seem to remember that Mackeson didn't taste that bad... however your pocket will be overjoyed to learn that nowadays, having imbibed far too much in the past, my drinking is limited to lime and soda which costs all of 50p a pint at our local pub! And now you also know why I can afford Seatern!
Returning to somewhere close to the thread (although nothing to do with water ballast): I wonder how many of you know that it's possible to build a wind powered vehicle that can travel directly forward into the wind, and even travel directly downwind faster than the wind. I remember seeing a small model demonstrating the possibility many years ago when I was a physics student. The model was of the cotton-reel-wheels and model-aircraft-propeller type of construction but worked very well.
Since those long ago days it appears that the technique periodically gets forgotten and then reinvented. See
http://en.wikipedia.org/wiki/Blackbird_(land_yacht)_ for a recent incarnation. It works fine for a land vehicle driven via wheels, in theory it should work for a boat driven by an in water propeller, however I suspect that, in practice, the inefficiency of the propeller plus the drag on the boat would be too great. However might it work for a propeller driven boat once lifted onto foils? America's Cup here I come!
Peter
ps just to confirm "there's nothing new under the sun" I've discovered it has already been done for a model boat - see
http://www.sailwings.net/windspinner.html - At least this demonstrates the upwind case, the downwind case is more challenging.
pps Andy, your Morbihan quiz reminds me of a TV sketch (?Not the Nine O'clock News?) which proved that penguins were as intelligent as humans. The premise was that penguins only fail IQ tests because of language problems. A penguin was lined up with a number of non-english speaking people (French, German, etc.) and asked questions in English and the humans scored no higher than the penguin - theory proved!