Interesting cold storage techniques

[peaty]

I read about a user who created an offline wallet using a list of 10 questions, the answers to which made up the passphrase. This is interesting because he doesn't have to remember the passphrase itself, but it can be recreated by him or potentially anyone who gets access to the paper, but only if they know him well enough. Anyone else have opinions or interesting takes on cold storage?

[canton]

I read about a user who created an offline wallet using a list of 10 questions, the answers to which made up the passphrase. This is interesting because he doesn't have to remember the passphrase itself, but it can be recreated by him or potentially anyone who gets access to the paper, but only if they know him well enough. Anyone else have opinions or interesting takes on cold storage?

I think that's actually quite clever. I'd add the following recommendations, which are part of my own my cold storage solution (bitcoinpaperwallet.com)

1) a paper wallet should look precious and important (so that if you die, it doesn't get discarded as trash)
2) a paper wallet's private keys should be physically hidden (though the passphrase technique is a substitute)
3) a paper wallet should be designed so that it can't be photocopied (which well-intentioned family members or lawyers might do on accident.)

The one problem I see with the "10 personal questions" is that it assumes that even a decade from now, anyone who knows you very well is someone you implicitly trust not to steal from you. This doesn't really reflect human nature and relationships so well since theft often occurs between family members, friends, co-workers, etc.

[CIYAM]

A similar method that I have developed is the following: http://ciyam.org/memory_key.html

The idea is to use a very vivid memory (the older the better as generally when you start to lose memories it is the more recent ones you lose first) and you could use something like a photo (to give you a date and time to add in) although better to use a memory that isn't what is recorded in the photo but perhaps an experience that happened to you just before or after it (which maybe you never told anyone).

I combine this method with a small password using "scrypt" (which is very hard to crack even for relatively short passwords) in the CIYAM Safe http://susestudio.com/a/kp8B3G/ciyam-safe which has been designed to let you do raw transactions in a 100% "air-gapped" fashion via QR codes.

[trumbadera]

I read about a user who created an offline wallet using a list of 10 questions, the answers to which made up the passphrase. This is interesting because he doesn't have to remember the passphrase itself, but it can be recreated by him or potentially anyone who gets access to the paper, but only if they know him well enough.

Depends on the questions. If these are bit guessable, you dont have much strong passphrase

[bzyzny]

Storing your wallet.dat on an encrypted flash drive is a good idea. it is possible to make a bootable linux usb drive that requires an encryption key just to boot it (root partition is encrypted). a nice option is to load the key on a file on a second flash drive, so that there is no weak passphrase used. this would require someone to gain access to both usb drives + your wallets passphrase in order to compromise your coins. Also could be used like a bank safety deposit box, where the trusted party holds one key and you hold the other, and both are needed for unlocking the storage.