>It may be Sunday but that's no excuse for resting your brain. Plus has been grappling hard with the strange weirdnesses of quantum mechanics lately, and we think that you should too. So get ready to be mind-boggled.
What would Christmas be without the unlimited eating? And even though you can't taste it, there's plenty of maths in food. Here's some yummy examples.
Is maths always true?
Find some animal maths behind door number 8.
There are nearly 7 billion of us now, but how many will there be by Christmas 2111? Find out behind door number 7...
Our new postcards are too lovely to keep to ourselves! Look behind Door 6 and find out how to get your own set...
It's Cyber Monday and apparently this lunchtime we will all be shopping online. In case you are hunting for presents today, you can find our mathematical suggestions behind Door 5.
The auspicious date of 11/11/11 saw the launch of a brand new YouTube channel dedicated entirely to numbers – it's hiding behind Door 4!