For those of you who haven't seen it before, Thorney Motorsport have been doing tests on fuels for a while now. Makes an interesting read ...
http://www.thorneymotorsport.co.uk/tuning/October_2008_Fuel_Test_Report.shtml
http://www.thorneymotorsport.co.uk/tuning/Fuel_Test_Results_Update.shtml
http://www.thorneymotorsport.co.uk/tuning/October_2008_Fuel_Test_Report.shtml
http://www.thorneymotorsport.co.uk/tuning/Fuel_Test_Results_Update.shtml