Unison is planning to take its campaign to raise the minimum wage to music festivals in Reading, Leeds and Glasgow this bank holiday Monday - with support from Sid and Nancy the motorised wheelie bins, Rosa the nurse and 12ft-high puppets of political figures including chancellor Gordon Brown and shadow home secretary Ann Widdecombe. The union also hopes festival goers will sign 250,000 postcards supporting its call for a £5 minimum wage. It plans to deliver these to Downing Street later this year.