Sorry, Stacey, I beat you to it! There's already a thread running about this DFDS 2012 offers now available through Camping Cheques.
The £37.00 is for a single crossing for car and caravan on a DFDS ferry from Dover to Dunkerque, so a return crossing £78.00 which is still really good value. Don't forget that you have to buy three Camping Cheques on top - but still at £13.95 for a campsite pitch for two people, car and caravan, awning and electricity, they are also very good value!
Unfortunately no-one has replied so it's already sliding down to the bottom of the page, so this post will draw attention back to what is a very good offer.