Such novel proteins may also hold the key to explaining Vibrio cholerae's great mystery: how a free-floating marine microorganism can turn into such a killer.

ECONOMIST: The cholera genome

Next we turn north, floating past the fragrant botanical garden of Lord Kitchener's Island and the domed tomb of the Aga Khan, high on a sandbank to our left.

BBC: The perfect trip: Egypt

Planetary Resources plans to take rocks floating aimlessly in the solar system and turn them into valuable commodities.

ENGADGET

One is to turn back the clock on financial integration: then pure-floating or semi-fixed systems might once again be used successfully.

ECONOMIST: One world, one money