Wikipedia founder: what copyrights should we buy with $100MM?

Here's a tasty tidbit from the Wikipedia mailing list: Wikipedia founder Jimmy Wales asking Wikipedians to suggest copyrights to buy and free with a $100 million budget:

I would like to gather from the community some examples of works you
would like to see made free, works that we are not doing a good job of
generating free replacements for, works that could in theory be
purchased and freed.

Dream big. Imagine there existed a budget of $100 million to purchase
copyrights to be made available under a free license. What would you
like to see purchased and released under a free license?

Photos libraries? textbooks? newspaper archives? Be bold, be specific,
be general, brainstorm, have fun with it.

I was recently asked this question by someone who is potentially in a
position to make this happen, and he wanted to know what we need, what
we dream of, that we can't accomplish on our own, or that we would
expect to take a long time to accomplish on our own.

Link

(via /.)