The best open source alternative to Vimeo is PeerTube, which is both free and Open Source. If that doesn't suit you, our users have ranked more than 100 alternatives to Vimeo and 11 is open source so hopefully you can find a suitable replacement. Other interesting open source alternatives to Vimeo are LBRY (Free, Open Source), DTube (Free, Open Source), IPFSTube (Free, Open Source) and YouPHPTube (Free, Open Source).
Free Video Sharing CMS. Start your own video sharing website with CumulusClips video sharing script. It's free and easy to use. You can build a YouTube clone where users can upload videos, rate videos, comment on videos, and much more.
This Youtube Mashup Turns Youtube Into A First-Year MTV Tribute : No Advertisements Music 24/7 Playing Music Videos. The Source Code is available from github here and is GPL'd: https://github.com/riseofthethorax/chann3lz.