You're thinking of Dave Gorman I'm certain. Very funny comedian and writer that has been on TV in the UK.

Wikipedia tells me this about Dave Gorman's letter writing, is this what you're remembering?

His second full-length show, Dave Gorman's Better World, was first performed in Edinburgh in 1999.[6] For the show he wrote anonymous letters to thousands of local newspapers and asked the public to suggest ways in which one man could make the world a better place. He then attempted to carry out their suggestions in order to determine their efficacy.