There are plenty of ways to enjoy game simulators that have more than one seat, but they're almost always of the bucket variety for one-on-one competition. Sometimes, however, there may be an occasion to share the experience on a bench.
Enter the vibrating "RumbleSeat" from BoomChair. It's kind of a loveseat for gamers that can provide, as Chip Chick says, either double the fun or double the queasiness. One convenient feature is that it can be hooked up wirelessly, which might avoid some equipment damage if things get out of hand. And for those of you who think two's a crowd, there's always the solitary "BoomPod."