I am toying with the idea of adding keyfiles to various things that I encrypt. However what's been keeping me from adopting them is guaranteeing that I don't lose the keyfile while still keeping security.
My issues is that with passwords if you think long enough and can try enough you will eventually remember it. Keyfiles on the other hand are gone forever if you lose them with <1% chance of ever recreating it.
Sure I can put the keyfile in 6 flashdrives and back the file up to multiple sites (can't put it with my normal backups as they are encrypted), but then you run into plausible deniability issues ("Hmm, why do you have 6 flashdrives that have the same single file?") and security issues (the more exposed something is by definition its less secure).
What are some recommended ways to keep a keyfile backed up and always available without compromising security and plausible deniability?