There are people letting to download Cinema 4d scene file free of charge. They even let you to use it on your commercial projects.
Mike Winkelmann from Beeple is a great artist who create and share a lots of Cinema 4d scene files. Honestly speaking I even downloaded most of the projects and carefully learning the techniques he used to create awesome animated videos. Most of them are simple techniques, you never tried. May be, but I learned a lot. So you can also download all these files and start experimenting.
|Property of Mike Winkelmann from Beeple|
Here is the link for download
Watch some of the videos
Impressed? Jump to his website and download the projects. Happy experimenting.