Adaptist makes a multi bayonet mount for Pentax DSLR cameras that enables Nikon, Olympus, Yashica etc. to be able to be mounted on the PK mount.
Nikon optics maintain infinity focus as do some others.
The camera can still use standard Pentax lenses with AF and full communication between the body and the lens........whereas other makes do with out AF and automations and lose the locking ability on the mount.
Link to their how to do it video:
that's what I call a clever little trick!