As you probably know, May is shopping month here at 10:10 HQ - so what better time to get behind a really great initiative from one of our biggest shopping sign-ups, Marks & Spencer?

M&S joined 10:10 back in March, and have been backing all manner of amazing environmental  projects. Now they're asking YOU to come up with a green shopping idea that you'd like to see rolled out across the UK - and are offering the prize of £100,000 for the environmental organisation of your choice for the best one.

Not wanting to sound cheeky or anything, but 10:10 could certainly use £100k, which would give the campaign a massive boost. If you've been sitting on a genius idea to reduce packaging or think you may be able to make wasted food a thing of the past, they want to hear from you. And so do we - once you've visited the Your Green Idea website, tell us about your idea by emailing hello@1010uk.org and we'll put the best ones up on the site.

There's not much time left to submit your green idea - the deadline is Sunday - so you'll have to be quick. And don't forget to mention 10:10!