New Year's Eve, Christmas, whatever. These mobiles (including the Mobius shown at top by Julie Frith, $150) would be great decorations for any winter party...and you can leave them up afterwards (which might make it OK to spend a little more on party decor). Or do the DIY version and make one yourself. Click here for good instructions for a mod mobile from Martha Stewart. More options below.
Aarikka Mobiles, $27-$39 at Finn Style
Tri-Lumen Large Mobile, $365 at the MCA Store