I hacked up the brainwallet.org sources and made it work for ssh keys. adam3us thought it was interesting, so I'm dropping the announcement here.
Same caveats as brainwallets, you need to select a good passphrase if you're going to use it [1], but it comes in handy if you're aware of the threats.
http://jwilkins.github.io/brainkeys
[1] http://www.homestarrunner.com/sbemail1.html