There were plenty of complaints about the accelerated time schedule to design the Scottish parliament, but that was leisurely compared to the new home for the Greater London Authority. Six architects have been invited to produce designs on Saturday 19 September. They will have just six hours to produce an image (in Dulux paint) of their idea, and will only be told the site on the day. Handy with a paintbrush are Will Alsop, Ted Cullinan, Jeremy Dixon with Edward Jones, Tony Fretton, Piers Gough and Eva Jiricna. The results will go on show at the.gallery@oxo at the Oxo Tower wharf.