TaxiGas is a means for taxi drivers and taxi companies to find cheap petrol and advertise their company free.
Just sign up and contribute some data to the site and your company will be listed in the "Find a Cab" section.
Type "Find a Cab" into Google to see how close to the top of the list TaxiGas appears (at time of writing, No. 1).
If anyone's going to find your taxi company via Google, they'll find you first at TaxiGas.co.uk.
Best Regards,
Richard