Make's Halloween project is a Cylon jack 'o lantern. You'll need a "Larson scanner," some LEDs, chrome spray paint, and a big pumpkin. Detailed instructions are in this month's special edition of the magazine itself, but its video should be enough to guide steady technical hands: "You'll probably want to put the scanner in a zip-lock bag"
Weekend Project: Cylon Jack O' Lantern [Makezine]
Why don't I ever think of these things?