Free and legal
Some links to media that are out of copyright:
Foremost, of course, is Project Gutenberg. (I remember the days when it was only at its old site.) As the world’s first digital library, it has been, for about 35 years now, rendering great service to mankind, publishing hundreds of free ebooks every year. It has nearly 20000 free ebooks available at the moment, and 2 million are downloaded every month. Look at etext 2852 for something slightly interesting ;-)
And then there is the Internet Archive. Apart from being the home of the immensely useful Wayback Machine, it also hosts a large amount of public-domain material, including books, radio shows, and movies. I’ve already seen movies such as D. O. A and Hitchcock’s 1934 version of The Man Who Knew Too Much (BTW, Que Sera Sera is in the 1956 remake, not this one) and plan to eventually seen Nosferatu, Battleship Potemkin and (just for the heck of it) Night of the Living Dead.
See Movies → Movies and films → Feature films → Sorted by popularity or look at the staff picks on the last page.
Another source of these movies (to save the archive.org folks’ bandwidth) is publicdomaintorrents.com.
A list of public domain movies is available on Wikipedia.
A lot more movies and books would have been in the public domain by now, if not for the deplorable Mickey Mouse Protection Act. Please take the time to also read Sprigman: The Mouse That Ate The Public Domain and The Online Books Page‘s informative page.