Bigfoot →
My favorite feature I ever added to Instapaper was footnote popovers. (I liked them so much that I applied them to every link in The Magazine, too.) Since then, I’ve wanted to write a Javascript implementation for my site, but I’ve just never gotten around to it.
Fortunately, Chris Sauve wrote Bigfoot, which does exactly what I want and does it better than I could have. It’s so good that I have zero desire to rewrite it myself, and that’s saying a lot.
I’m going to be tweaking its styles a bit and adding it sitewide soon. Until then, I’ve embedded it manually in this article for testing.