Things that Defy Classification but are Really Useful

Boat Hooks from Davis Instruments

Key Buoy from Davis Instruments - drop it and sail back for it!

Tell-Tales and sail-mounted air-flow tells from Davis Instruments

Aquasafe Waterproof Bags for mobile phones etc from Echomax

Aquamate Smoke Hood from Echomax lets you escape from smoke-filled spaces.

Watches and Wallets from Gill

Telescoping paddles and pannier-style cool bags to hold ice and drinks (or other things) on jet-skis, motor bikes and the like. From Kwik Tek.

Boarding ladders from Plastimo.

Outboard Motor Mounting Brackets from Plastimo.

Mounting Systems for Marine Electronics from Scanstrut.

Wichard have a Boom Brake that owes its inspiration to an abseiler's figure-of-eight.

Wichard also have an extensive range of boat knives with semi-serrated edges and useful things like marlin-spikes and shackle-keys.

Windex make the best-known wind indicators in the world.