O3D is an open-source web API for creating rich, interactive 3D applications in the browser. This API is shared at an early stage as part of a conversation with the broader developer community about establishing an open web standard for 3D graphics.
The latest release is O3D Release 0.1.40.1
O3D is available in Internet Explorer, Firefox, Chrome, and Safari and works on any Linux, Mac, and Windows computer that meets the minimum hardware requirements.
You can watch the sample here http://o3d.googlecode.com/svn/trunk/samples/beachdemo/beachdemo.html
You can download O3D from http://code.google.com/apis/o3d/