Eye Toy: Groove is proof: Disco does not suck anymore. Disco is wicked excellent. Disco is the bomb. Disco is great.

You may not have heard of the Eye Toy yet. That is too bad. Here is a primer for you. The Eye Toy is a little camera that plugs into your PlayStation and sits on top of your TV. It comes packaged with a game called Play, which is eight layers of ridiculous fun in and of itself. You will come to know and love Play, because you must have an Eye Toy to play the new title, Groove. You will especially love Groove.

Like its predecessor, Groove asks you to do the one thing you never do while playing video games: move your body. To play is to have your heart racing and your chest heaving for breath and your arms flapping about like chickens recently separated from their heads. It is a dilly of a workout, this thing.

If video gaming for you means sitting motionless in your basement for hours, controller in hand, moving only to grab a fresh handful of Bugles and shovel them into your face, or possibly to glug another mouthful of Grape Crush directly from the 2L bottle, or maybe once in a while to rotate your hands a little and massage the kinks out of your abductor pollicis brevis muscle, it will kick your ass. If you play soccer three times a week, it will also kick your ass. It will probably kick your playmates' asses first, however.

The game is all about dancing. Or, rather, it is about a curiously stiff-necked thrashing-in-the-air, carried out in time with the beat of some fabulous old disco tunes. Here is how it works. You stand in front of your TV set with Eye Toy pointed at you. Your gorgeous image fills the screen. At the edge of the picture, little target things float expectantly.

Music begins to play. Little glowing ball thingies appear at the middle of the screen, each moving quickly toward one of the targets at the edge. They are staggered so that each one hits its target just in time with the music. Some coincide with the kick drum, some with the snare, some with little bass flourishes.

The idea is that you must wave a hand over each target at the moment of impact. The end result is a kind of frantic semaphore, with arms thrusting sharply at odd angles, accompanied by a little involuntary toe-tapping or hip-swaying. It looks terribly dumb, but it is so much fun that you will not mind, even though you can see right there on the screen how dumb you look.

If you are very good at swatting the targets, and if your timing is exquisite, the game will heap on the praise. It will fill the screen with colourful psychedelic swirlies. It will blur and stretch your picture, giving it a shimmery glow that disguises your blotchy imperfections and makes you look cool. It will give you an "A."

If you are not any good you will fail and the song will end prematurely and you will have to yield the dance floor to someone else. But then, this is all part of the fun, getting to sit down on the couch and catch your breath and heap Bugles into your face while someone else does the convulsing semaphorist and tries to look stylish and rhythmic.

Groove is a party game. At the bare minimum it is an enjoy-with-friends game. It is quite possible to play it on your own, and to have a good time doing so, but you should try hard to avoid doing that. Why? Because looking like a terrible dork all by yourself in your basement is heartbreaking. Doing it in front of friends and relatives takes the sting away and spreads the humiliation around.

Also: If there are others in the room, there will be somebody to call in the defibrillator truck when you keel over from over-exertion.