h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

It is possible to play the game of "battleships" over the office tannoy. This works best in large companies where tannoy announcements are common and people do not know everyone else! The gameplay is based on a standard grid, and the moves are encoded in a series of tannoy announcements:

In a company that uses 4 digit phone extensions, for example, the following exchange might take place during a game:

Player A: "Will Mr Null please call extension 2714"

Player B: "Will Mr Null please call extension 2767"

Player A: "Will Mr Pling please call extension 2713"

This translates as player A reporting a miss from the previous attack, and requesting an attack on square (1,4). Player B reports a miss and attacks square (6,7), and then player A reports a hit and attacks square (1,3). Other names can be used to indicate the destruction of a ship, or this can be encoded as additional information:

"Will Mr Pling please call extension 2713, *urgently*"

More plausible names should of course be used in any real implementation, preferably with more than one for each meaning. They should not be the names of people who might actually hear the messages!