Hampshire's Milestones Museum has added Windows Media Video links for all its text content, so that people who primarily communicate via sign-language can click and get a video of the text being signed. Neat, and another example of just the same information being presented in different ways - a bit like the images-versus-other-content design in XHTML 2, below.
1. It would be cool if anyone could add their own "interpretation" or translation of any content, anywhere - like a cross between a Wiki and an Annotea service.
2. This is exactly where we're heading, I hope. Along with/instead of "BSL" links by content, you could have a "choose your language" link which allows you to replace the english text with whatever you like. It's getting there, bit by bit.