Air hockey tables are large, immobile, and somewhat expensive. Definitely not the type of game you can take with you to work or school.
In the anywh-air hockey system, it is the puck that forces jets of air out the bottom, creating the cushion of air between it and the table. A small electric motor encased in a thin, lightweight cylinder sucks air through the slats top and pushes it through small slats in the bottom. Photoelectric plates on the top and the bottom of the puck allow the puck to determine which direction is up, influencing the direction of the motor.
(Of course, you'd need an extremely small motor and ultra lightweight materials, not to mention machinery that could handle the extreme impulse from the paddles, but I'll let you engineer types worry about the plausibility of that.)-- Cuit_au_Four, Oct 28 2005 You'd need some sort of way to prevent the disk from flipping over, but otherwise an interesting idea. The main problem would be in having a game that lasts longer than 60 seconds (when the battery charge wears off).-- Adze, Oct 29 2005 Add a small skirt around the edge on each side to turn it into a hovercraft - that'll improve the efficiency (play time vs battery charge) as well as giving it some tolerance for less-than perfectly smooth surfaces.
Once you've done that, I don't think the weight of a decent battery and robust construction would be such a problem. And a simple mercury switch should deal with the up/down OK.
In fact scale it up to full-size, play it on a grass field and whack it with real hockey sticks....-- BunsenHoneydew, Oct 29 2005 Forget the batteries, have the action of moving the puck generate the electricity like a shake flashlight. +-- 2 fries shy of a happy meal, Oct 29 2005 Anything that has to do with airhockey (in a positive way) gets my vote. Lightweight, cushioned bun for you.-- Trickytracks, Oct 29 2005 I saw some material a while ago on ultra small turbines being used to generate electricty using gas. The problem was waste heat, but in this case you could vent the gas stream and waste heat. Search "tiny turbines" on google finds it.-- paru, Aug 15 2006 random, halfbakery