JMF 'home page'
http://java.sun.com/products/java-media/jmf/

HTML JMF API
http://java.sun.com/products/java-media/jmf/forDevelopers/playerapi/packages.html

HTML guide to the JMF Player
http://java.sun.com/products/java-media/jmf/forDevelopers/playerguide/index.html

NASA multimedia gallery
http://www.nasa.gov/gallery/index.html

Sunsite Japan Multimedia Collection
http://sunsite.sut.ac.jp/multimed/

Has neat video search engine
http://www.mediachannel.com/

Bird calls from the Australian National Botanic Gardens 
http://www.anbg.gov.au/sounds/

some free & (legal) MP3s
http://www.epitonic.com/