Holiday Easter Egg in Google Spreadsheets - can you find it?

Hi,

After fixing loads of bugs in this most recent release, one of our engineers needed a change of pace and spent a lunch break doing something festive and fun. He created a tiny "easter egg " in our product, just for the holiday season and just for you. See if you can find it!

We'll give you one hint: it's a function. If you think you know which one were are talking about, submit your answer through this form. First 15 people who come up with the right answer will get Google Spreadsheets holiday schwag.

Cheers,
Google Spreadsheets Guides Chandler, Christine, June, Marie and Steve