I'm definitely doing this this year!
I'm with Colleen on the battery stock- up too. I'd also add to that good ol' loo roll and dishwasher tablets/ capsules / whatever you use (the dishwasher really earns its keep around Christmas and I get through more then. Washing up liquid is useful too.
On a more delicate note, ladies' sanitary products are wise to have in- as well as things like extra paracetamol, asprin/ indigestion tablets etc. Toothpaste is a good one to have plenty of.
Don't forget pets, either! Make sure that they have enough food/ bedding (if you have hamsters/ rabbits/ small animals etc)