Constellations 20 oz Heat Reactive Mug
Item # 1001963
$ 14.99 each

Nothing says cozy like curling up with a hot beverage and look up at the stars. 
This mug allows you to do both from the comfort of your living room.  Before you add your drink to the mug all you see is a star field.  Then once the heat starts to spread the constellations apear right before your eyes.