We recently launched http://sketchfab.com, a free service to publish interactive 3D models online with WebGL and HTML5.
We have exporters for blender, 3Ds Max and Sketchup, to upload in 1 click directly from within these softwares: http://blog.sketchfab.com/tag/exporters
We are looking for people to help us code an exporter for Cinema 4D. If anyone is interested by getting involved, please let us know at firstname.lastname@example.org
The Sketchfab team