My demands for “reverse” glasses have gone unserved, but I made a bookmarklet that provides the same effect: “flopping” a video horizontally.
- Install the SwitchStance bookmarklet, for which you’ll need a modern browser that supports CSS transforms on video elements.
- Opt-in to YouTube’s HTML5 trial
- Load up any video without ads (here’s one of Matt Hensley skating)
- While the video plays, click the bookmarklet.