Enclave: An Unpickable Lock
This is clever to break the unlocking into two phases.  I’m not a serious lock picker so probably this idea is widespread.<p>Many years ago I imagined a lock in which the mechanical action of pushing the key all the way in would engage a lever that engaged the pins (until then they would just float and provide no information to the lock picker).  Using rotation to achieve this looks simpler and more (mechanically) robust.