When you use something like Electrum to generate a brain wallet, the passphrase is the seed. From this seed, the app generates an unlimited number of addresses, public keys, and private keys that can be deterministically re-generated, given the passphrase. So in this case, you can have one "brain wallet" (the passphrase) but an unlimited number of public keys generated from that seed; and revealing any of these public keys should be perfectly safe. Right?
Could I choose my own passphrase to do that? I don't trust those randomly generated passphrases.
But I want to be able to use a passphrase to pull up my private key without using software that could become deprecated or non-standard overtime. I would like to be able to recall my passphrase 40 years from now, and the standard generator will pull up my offline savings account without worry.
just use brainwallet.org and save a copy of the site, should it go down.