The line between gimmick and innovation is sometimes hard to draw. Game purists look down on specialized peripherals, and while I like my shotguns and dance-pads in single-purpose arcade games, I rarely think they’re justified in a multi-purpose home system. Maybe I know too many people who bought the Power Glove. This Mattel peripheral was introduced in 1989. It worked with the Nintendo Entertainment System, but not as well as it worked for Fred Savage in the movie The Wizard.

The film — which was essentially a 100-minute commercial for the useless peripheral — went so far as to have one character say: “I love the Power Glove. It’s so bad.” And while the list of bad examples of gimmicks and cash grabs is long and illustrious, I’ve decided to focus on a few peripherals I put on the innovative side of the line.

My pal Sally told me about the Tekken Torture Tournament, a project from Los Angeles-based C-Level, which has been staging rather unusual competitions in art spaces worldwide since 2001. The self-described “cooperative public and private lab” wires “willing participants” with electrodes from a modified console, and the fighting game gives them electric shocks when their on-screen avatar gets hit. It’s a simple and funny idea that’s kind of a science-fiction story brought to life, camp and all.

The C-Level lab also stages Cockfight Arena, in which two people don chicken head and wing peripherals and peck away at each other. As their avatars do the same on the screen behind them, the crowd eggs them on. The website states that “gambling and smoking will be permitted,” and so there’s more than new interfaces being experimented with here — as with TTT, they’re pushing buttons of a social kind as well, using gaming to play with the forbidden.

If that’s the do-it-yourself model of successful peripheral-building, the EyeToy is an example of a successful corporate model. Produced by Sony for their PlayStation 2, it looks like a tiny security camera, squatting on your television and watching you with its glowing LED eye. When you start it up, it projects you onto the screen. The tutorial walks you through the basics, the most surprising being that you are the controller. The EyeToy tracks movement so that you interact with the games by moving around.

In one of the 12 mini-games the device comes with, a soccer ball falls from the sky and it’s your goal to keep it up, either by heading, kicking or kneeing it. In Kung Foo, you beat back ninjas who leap at you from all sides, deciding between cool-looking chops or more effective but gawky arm windmills. There’s also one I imagine kids loving: you have to slap rats off clouds as they burp and fart and waggle their bums at you.

These twitch games are fun, but Sony’s London Studios are to be applauded for going a few steps beyond that with some of the mini-games. The beat-heavy soundtrack to most of the games is given a break in Wishi Washi, where you wash windows to an ol’ 1920s-style toe-tapper. Mirror Time has a simple concept — touch the green circles, avoid the
red — that twists your brain by showing you a mirror image of yourself, then one that’s bisected, and gives you scant seconds to rethink your bodily impulses. Beat Freak is a music game rather like Dance Dance Revolution, except that you point at the overhead lights in time with the beat rather than stepping on the right foot-pads.

This points to a shortcoming of the EyeToy — it’s really optimized for waist-up. A well-lit room is also required for all the player’s movements to be detected, a shift for gamers who are irritated by monitor glare. But quibbles aside, there’s a tremendous amount of potential here. One thing hinted at in the mini-games that merits more focus is the ability to distort or play with the player’s image. In Wishi Washi, when you finish washing a window, the camera pulls away and moves up to a higher floor; the feeling of leaving your body is really interesting. The Kung Foo game also includes some slow-motion effects where your arms blur. If there was a tighter connection with the gameplay, it’d be really satisfying.

If they develop games for two players simultaneously — though that may require a separate EyeToy to effectively track two players — it’ll add a whole new physicality to the competition. There are plenty of party videogames that people enjoy in a social setting, but this has an added bonus: it’s as fun watching someone else play as it is to play yourself. Watching someone flail around is a lot more entertaining than the sight of two people grimly mashing buttons.

Potential aside, the fate of the device will be decided by whether game developers decide to take up the technical and creative challenges it offers. With 2.4 million units already sold and 70 million PlayStation 2s out there, I imagine developers are drooling.

But that may be a side-effect of too much Tekken Torture Tournament.