What is a non-executive director?

I've been perusing the appointments section in last weeks Sunday Times and I couldn't help but notice the number of "non-executive director" vacancies available. What exactly is a non-executive director? Sounds like someone who does f*ck all to me. For example...

Non-executive director for The Christie cancer centre which is an NHS Foundation Trust... so a job for the state, yes?

The bulk of the advert describes what the organisation is. Then a short paragraph says

"Working with our board, you can help to keep us moving forward. You'll need senior level experience gained in a complex organisation (sounds woolly to me) and the vision and commitment to share responsibility for the entire organisation, including our successful hospital charity, the second largest in the UK."

Now this is the bit that beggars belief. £12,850 pa. for 2.5 days a month!!!!!!

We are told that savage cuts are going to be made across the public sector and these f*cking retards are advertising for some w*nker to spend 2.5 days a month doing f*ck knows what for £12,850 pa. And you bet your life the pr*ck that gets this job will probably have several others of the same ilk.

On the same page is an advert for a similar job at the BBC.

I wonder if I should apply?

Rant over.