I heard several years ago that Lockheed Martin was looking at new seaplane designs. In 2003, seaplanes emerged again as an element of a sea-basing strategy - providing sea-bases with a high-speed, heavy-payload link to safe land bases a long way off. However, nobody at Lockheed Martin seemed to want to talk.
However, a newly unearthed paper with two Lockheed Martin authors shows some interesting potential features. The proposed SeaMax is a twin-hull design - apparently dating to equally little-known 1970s studies by Lockheed-Georgia - powered by two F117 turbofans.
A C-130 floatplane development - studied in the late 1990s, apparently at the instigation of the special operations community - would serve as the technology demonstrator for the project.
Incidentally, the third author on the paper - Basil Papadales of Washington-state consulting company Moire Inc - is an ex-Boeing guy, and was at one time the manager of the Condor UAV program.
Pics: Moire
http://up-ship.com/blog/?p=4570
Turns out one iteration of the design *does* feature floats just like those in the 2006 design.
By the way, the linked PDF file is not longer available... they've scrubbed their website. Did you save the file somewhere accessible?