The Internet Archive calls itself “a non-profit library of millions of free books, movies, software, music, websites and more.”
It’s the home of the Wayback Machine, a search engine that lets you hop back in time to see any website as it appeared years ago, such as the humble beginnings of this site:
But the site goes way, way beyond archiving websites. I discovered it when I was searching for royalty-free video footage that I could use in presentations (now I get most of mine from this great site). It’s a mixed bag of content you can just look at and works you can use personally and commercially. You just have to search around.
Some of my favorite areas: