How do you plan to make them (un) recoverable?
Armory has (or will have soon) an awesome feature built into the paper backup system that allows an M of N recovery. Fully customize-able.
I plan to print 10 sheets of paper that each have a piece of the puzzle to recover my cold storage wallet. It will require 7 pieces of the original 10 to recover the wallet.
6 of them get distributed to family and friends with instructions to hold onto them until I die.
4 of them are to be in the will itself, this way, the other 6 can never do anything before I actually die (not that I couldn't trust those people).
That's a neat idea.
It could be used with all your important logins. Maybe another use for your wallet?