Rewind to London in 1850 and the first public toilets which required users to insert a coin to gain entrance were born, along with the phrase ‘to spend a penny.’ Fast forward to 2007 and Londoners can now spend 25 pennies to use a cellphone operated, location based, SatLav service that has just been introduced in the West End by Westminster City Council.

The shopping capital of Europe, London’s West End includes such famous places to do some retail therapy as Oxford Street and Regents Street and can boast world renowned shops such as Harrods. With crowds guaranteed at this time of the year, being able to quickly locate a loo might not be high on the list of priorities for most shoppers – until they need to quickly locate a loo that is! Unless you have a portable GPS satnav unit complete with a public lavatory location Points of Interest file pre-loaded, the term desperate housewives could take on an altogether new meaning.

Which is where Westminster City Council and student Gail Knight enter the fray. Gail won a design innovation competition sponsored by the council with her SatLav concept. Using the ability of a cellphone network to know where the caller is, or at least in which network ‘cell’ the call is originating from, the system can quickly let them know where the nearest public toilet to them happens to be. All the user has to do is send a SMS text message containing the word TOILET to the SatLav number (80097 if anyone in the West End of London is reading this with legs crossed) and with 25p duly added to their phone bill or deducted from their phone credit, the location of the nearest of the 40 loos operated by the council is texted back.

According to Westminster Council up to 10000 gallons of urine is at risk of ending up in the city's streets and alleyways through irresponsible and antisocial behaviour. Councillor Alan Bradley comments “From today nobody should ever get caught short again, and we understand how important that is, be it for a young mum with children in tow, older people or friends on a shopping trip or night out."

Well, that's a relief...