It's just a password manager (although, with some firmware and client tweaks, it could be a signing device), and only $45.

I've never heard on moolti-pass before but it looks legit! The whole knocking on wood thing is weird, but they seem legit about being open source, as opposed to being like most companies that claim to be open source because one component is open source. I saw mooltipass has published kicad files.