Which arts membership schemes are good value?

From the Tate to the Southbank Centre to the Barbican, tell us which schemes offer good perksEvery week a Guardian Money reader submits a question, and it’s up to you to help him or her out – a selection of the best answers will appear in next Saturday’s paper.I’d like to get my partner an arts organisation membership for Christmas (we live in London) as I’m keen for us to expand our cultural horizons. He likes the theatre, films and art. However, I don’t want