GitHub repos, or a SVN could work for this system... I also have a buttload of hosting where I can store all of this content if needed. Google Drive/Dropbox would work, but this would have to be "owned" by someone or a few people. We don't need dicks everywhere now...
Also, here are my contributions to this pack.
http://www.tophattwaffle.com/downloads/realworldtextures-2-textures/
http://www.tophattwaffle.com/downloads/water-source-textures/
http://www.tophattwaffle.com/downloads/mario-world-textures/