Okay, the ":target" psuedo class just blew my mind. Not necessarily for modals (which I don't particularly like) but I can think of a lot of other uses. Edit - Apparently it's been around for several years. Not sure how I missed this.
Likewise! That's actually the reason I submitted the article.
I used it several years ago to create deep links to a list of audio files on the homepage of a site I built. By default the controls were hidden, but if you clicked one of the titles in the list it would show the controls and update the url so you could share a link to that specific item with no JS required.