Ubuweb, the website that serves as an archive for all sorts of interesting avant-garde writings, video and music, is a site that many people who read this blog would enjoy exploring.
It has a monthly feature called Ubuweb Top Ten in which somebody is invited to list their ten favorite items on the site. I've never been invited to contribute, but here, anyway, is mind:
1. Conversations | William Burroughs, Brion Gysin, Timothy Leary, Les Levine, and Robert Anton Wilson (7:10) This is about it for RAW material, but search the Internet Archive.
2. Music of Frederic Rzewski. Includes many of his best pieces, such as "Coming Together."
3. Joseph Cornell's Rose Hobart. The surrealist artist turns a hokey adventure movie into a dreamlike work of art.
4. Igor Stravinsky Chamber Music (link from the site), good collection of pieces.
5. L'Étoile de mer (English: The Sea Star), movie by Man Ray. Kind of an illustrated poem, with subtitles in English.
6. Contemporary Polish Music. The Penderecki piece is the most famous, but I also like the music by the other composers.
7. György Ligeti. Aventures-Nouvelles Aventures, Atmosphères & Volumina. Some of the important composer's best pieces.
8. Luciano Berio — Berio Conducts Berio. Another interesting modernist composer.
9. Steel Foundry, by Alexander Mosolov. Historic recording of famous piece by Russian composer repressed by Stalin. (Scroll down.)
10. The Music of Lou Harrison. (Scroll down). Good introduction to music of West Coast composer I like.
Check out the Ubuweb Top Ten archive for other suggestions.