Electrum version 2.0 and higher supports the creation of
multi-signature wallet types. I recommend that Tails upgrade their
Bitcoin donation address to a multi-signature address for increased
security and redundancy. A multi-signature address requires m of n
signatures from separate wallets in order to spend the corresponding
Bitcoins. A partially signed transaction is created and sent to one of
the cosigners for completion. You can setup a 2 of 3 multi-signature
wallet to protect against one of the cosigners' wallets being lost or
destroyed. In order to set it up, you need the master public keys of
the cosigners' wallets. The cosigners are usually other leaders of the
project or it can be an offline wallet. The resulting multi-signature
addresses begin with a 3 instead of a 1.
Please read the Electrum documentation on multisig at
http://docs.electrum.org/en/latest/multisig.html . If you have any
further questions, email me.
