Mike Jones wrote:
http://www.shuttlebike.com is floats that attach to a bike, with a
pump driven off the bicycle wheel to inflate it.

Cwor! I *like* it!

The basic idea has been invented before. This time they seem to have
solved the long-standing problem of getting some gearing into the
system so that the pedalling effort is not disproportionate (i.e.
tiring and ineffective).

But this is done bz clamping a roller against the back wheel. I'd want
to knowmore about this, in terms of tyre or rim damage.

But it does look like fun.