I cannot recommend these streams highly enough. It is a wonderful option to the same 40 songs played in the same sequence all day long. And a far better option than so-called "talk radio" and the farce that has become, thank you Jerry Springer, Limbaugh and Jim Rome...
Anyway, they have a nice SF selection and I am assuming it changes on a regular basis. Plus it's free!
http://www.bbc.co.uk/iplayer/radio/bbc_7/drama
Lots of other genre's to choose from...good background noise while working.