Help me find footnotes for ORG's paper on BBC DRM

I’ve just finished a draft of the Open Rights Group’s response to the Ofcom consultation on allowing the BBC to lock its broadcasts with DRM. I’m just looking for a few references to fill in my footnotes. If you have a good citation for any of the following, post it to the comments!

1. Stats on US investment in HD broadcast content
2. How much economic activity does free/open source software generate? Got it! — thanks, Jan!
3. References to BBC children’s content that encourages remixing Got it! — thanks, CDE!
4. History of the controversy after the introduction of Zenith’s first TV remote