Yeah, it'd be cool....but it's a lot of real-estate to take up. Plus, you'd need to hack the motion base to really take advantage of it and all those PS2's and 3 copies of the game will cost a chunk of change too! But, if you have the space, cash and time to devote to something that plays 3, maybe 4 games max, it would be an interesting toy.
Or, you could just buy a DLP projector and sit close to the resulting 10' screen. I think the effect you get from that is just as realistic. I played Halo like this for hours and had a really weird "returning to reality" experience when I forced myself to stop

. It was the first time I felt that level of immersion in a game.
Driving games played like this are pretty realistic too, plus you can watch a movie on it afterwards

.
RandyT