In the case of 100+ BTC. I's very simple. 2 things. One, you want to keep an eye on that, so as they don't just disappear over night. Two you want that off-line, far from the prying hand of hackers!
My suggestion, is break it down into 4 paper wallets, generated off-line, 25+ each. Each using a unique pass-phrase or password. Paper wallets are stored in a plastic zip-lock bag for moisture protection. The private keys associated with their corresponding public key should be copied to a SD, USB, or a removable media device by an off-line computer, and that to should be zip for moisture!