There are traditional Jack-o-Lanterns with a face carved on the front and a candle inside. Then there are art pumpkins, with skillfully carved scenes of all kinds. A third category contains the geeky Jack-o-Lanterns that do something strange and unexpected, like the ones we are looking at today.

1. RoboPumpkin

Yes, this is a real pumpkin! The RoboPumpkin is from artist Joseph Paul Johnston. The metallic spray paint makes it look like aluminum. A detached face, a few spare parts, and a string of Christmas lights make it into a robot. His Flickr set describes the steps to make it.

2. Snap-o-Lantern

The Snap-o-Lantern is a small robotic pumpkin that opens its jaws to reveal sharp, snaggly teeth! It’s almost a cross between the prank chattering teeth and a jack-o-lantern. A small battery-operated servo motor runs the hinged jaws, and LEDs light up the eyes. See a video of the Snap-o-Lantern in motion.

3. Project Squirrel-o-Lantern

The neighbors complained about squirrels eating their jack-o-lanterns, but this guy decided to let the squirrels do the designing work for him. He left an unlit but partially-cut pumpkin outside and enticed the neighborhood squirrels to come and carve a Jack-o-Lantern face. You’ll have to admit they did a pretty good job!

4. Cylon-o-Lantern

You can carve a pumpkin to look like a Cylon, but you need the lights running back-and-forth to make it really resemble the evil robots from Battlestar Galactica. Evil Mad Scientist Laboratories rigged a group of six LEDs linked to a KITT Scanner Circuit. See the finished product in action in this video. Science fiction fans might also enjoy trying a Dalek Pumpkin.

5. Steampunk Pumpkin

The Steampunk Pumpkin not only has the steampunk sensibility with its brass fittings, it also blows fog out of its ears! The fog machine is controlled by a motion detector, so the show starts when someone approaches the pumpkin. The lights inside change color, too! See the Steampunk Pumpkin in action in a video at Instructables.

6. Rovin’ Pumpkin

The fertile minds at Evil Mad Scientist Laboratories have announced their Halloween pumpkin project for 2009. The Rovin’ Pumpkin is a simple robotic pumpkin, that will sit still for a while, then suddenly move around on wheels, while its glowing green eyes scare the wits out of everyone.

7. Pumpkin Skull

Ryan McFarland made this Skull Pumpkin which incorporates the pumpkin guts for added gore. The eyes are illuminated with LEDs.

8. Dark-detecting Jack-o-Lantern

Batteries and LEDs make a Jack-o-Lantern easy to deal with compared to candles. Next innovation; make your pumpkin turn itself on and off! See instructions for equipping yours with photosensitive lights. You don’t even have to be home for your lantern to light up at night.

9. Punkin Chunkin’

Punkin Chunkin’ is a sport of a sort where competitors sling pumpkins as far as they can using a trebuchet or catapult, or shoot them with a canon. The World Punkin Chunkin’ Championship will be held November 6th, 7th, and 8th in Delaware, but there are other local events around the country. Image by Flickr user NickG-B.

See also: The Art of the Jack-o-Lantern, Do It Yourself Molded Pumpkins, and A Dozen Pumpkins.