Ships is the first real use of Google Earth as a game engine. All you need to do is install the Google Earth browser plugin then load their plugin.

The use of the word "simulation" might be overselling it a tad. The controls are rudimentary at best. There is no collision detection in this first release so you don't have to worry about running aground. This isn't Ship Simulator so you hard core maritime types don't be too disappointed. The draw here of course is Google Earth and -oh yeah- it's free.

You can pick from 3 different barges, a re-fuel ship, a cruise ship, a container ship, and even an airship. The ship models are pretty realistic and the cruise ship is a pretty good version of the Queen Mary 2.

For a first release of a free product in an environment with such potential, the thing rocks. And since it runs in a browser you can play it at school or the office. - Not that any of you would be doing that.

Here's a cool video of highlighting the controls and a few of the ships you can drive.