Have you seen the Ten Stores event? It's a sponsored walk visiting 10 London shops like Selfridges and Liberty with special offers and limited edition things at the featured shops on offer to participants.
Thought I would mention it in case anyone wanted to do a charity event that was not about running, bungee jumping etc 
And Hope and Homes is an amazing charity…and there is champagne…and Claudia Winkleman…and shopping!