Michael Porter has a handful of designs on his web page, but the one that really catches my attention is the "Live Anywhere" Boat. He has created a craft designed around world cruising, including about 95% of the European canals, but instead of the standard "luxury" yacht features with tons of accomodations, etc., making it a floating home and workplace for a couple. Work from the boat and move around as you wish. With modern telecommunications and the opportunity to work "anywhere" via the net, this becomes more and more practical.
His 35′ Steam Yacht is also a nice looking, traditional craft. Steam power? Never even thought about it in this day and age. He comments that its quiet… hmmm.