EFF blog post: https://www.eff.org/deeplinks/2011/06/eff-and-bitcoin
RE: refunding donations by proving you own one of the private keys that donated: interesting idea! Anybody willing to write code to do that? Could be a fun project... (find all the transactions that donated to EFF, dig out the public keys, come up with a way to sign/verify a message with private key proving you own a public key, then keep track of which donation transactions have already been refunded)