I was surprised to see that YouTube now automatically creates a 3D-representation of uploads, to be watched either with anaglyph glasses (red/cyan or red/green), or cross-eyed, or with an auxiliary mirror !
It works surprisingly well, at least the test I just lploaded:
After a short pause, there will be a small 3D icon lower right, click that to switch on 3D, and adjust the settings.
Also, I joined Vimeo (the free version) to check if the comments on quality have any basis, and I think I can see a slight difference in Vimeo's favor. (In 720p, the free Vimeo doesn't allow 1080p...)
Compare for yourself, if you're interested; I uploaded exactly the same, original file:
Maybe the difference is even more noticeable in Vimeo Plus, which costs $60 per year? (At least you get 1080p for that... )