Make Your Own Xmas, says Bob and Roberta Smith18.12.2008 Tate Britain invited Bob and Roberta Smith to decorate their Christmas Tree. Smith decided to make a new tree out of recycled material collected from the gallery. Continuing the eco-theme, he invited his friend Tim Siddall from Electric Pedals to engineer a system for powering the Christmas lights - using a selection of second-hand bicycles. We caught up with Bob and Tim in Bob’s studio in East London, where they were preparing for the exhibition and sung us a song. Later, we asked enthusiastic bike-peddlers about their best and worst memories of Christmas.