Google has released a couple of neat easter eggs for the holiday season, similar to the Starfox-inspired "Do a barrel roll" trick from a couple of months ago that sends your search results page spinning. First, searching for the phrase "Let it snow" gives you an even more impressive animation alongside the Dean Martin links you'd expect. It's worth letting it build up for a while too, and you should try clicking and dragging across the screen.
Second, there's also a treat in store if you search for "Hanukkah," which Google has put live just a couple of days in advance of the start of the festival. Nothing yet if you search for "Christmas," but we'd wager that something will show up in a similar vein by this time next weekend.
Update: Sure enough, typing "Christmas" or "Christmas Lights" on the main Google search page brings up a string of lights. Thanks, Darren!