This reminds me of a product from the 90's where it let you leave post-it style notes on any website. You could then turn the nodes on/off for any given site.

This reminds me of a product from the 90's where it let you leave post-it style notes on any website. You could then turn the nodes on/off for any given site. Anyway, that was a great product, so I'm glad to see that you're thinking around similar lines. A meta-commenting system that runs any site is a great idea.