I ended up memorizing my home's old WEP key simply because, since I was the "tech guy" in the family, everyone would ask me whenever they needed to add a device (never mind that I was mostly just going to the password booklet and reading it out). Eventually I just stopped needing to look it up. I've since used it in some places, blended with a mnemonic for the specific site. 10 hex characters plus a string might not be the highest-security thing, but at least it's not going to fall to anything less than brute-force.