raw.pixls.us hosts raw files of all digital cameras with a Creative Commons Zero license. In their own words

> raw.pixls.us is used by darktable for regression testing of rawspeed and by RawTherapee. It is available for any projects that need access to a library of raw files.

They have a simple list of dos and don'ts. The submission process is a simple file upload. No account required nor name. There is also a list of cameras they are looking for.

Everyone who open source software or needs a freely-licensed raw file should take an interest in this project.

https://raw.pixls.us/