I have seen a bunch of these before, but the serial connections limit you to the gaming platforms available at the time, and they have limited buttons to allow for games that require more control.  X-gaming has taken care of those worries with their new ($199) Tankstick + Trackball that features 2-player head to head style gaming along with a trackball in the center to finally play those old school classics like Centipede and Missle Command the right way!  As far as connectivity, the cables are sold separately depending on what system you choose as the platform.  They even throw in 18 classic arcade games in the package.  Cool deal!