Any obscenely over-the-top holiday lights display on someone's home. Often done in an insanely competitive, anti- "peace on Earth, goodwill towards men" desire to outdo and one-up the neighbors.
Shawn: I haven't had any sleep in days. My neighbor's Griswoldian Christmas display is so freakin' bright it's been keeping me up all night. AND it's draining so much power it caused a black out in my neighborhood last night, so my alarm clock didn't go off!