It's easy to assume a knife covered in rust is bound for the trash heap, but rust is typically just on the surface of the blade waiting to be removed, and high quality blades can be brought back to life with a little elbow grease.
Chef Jun Yoshizuki of Jun's Kitchen knows how to resurrect rusty blades, so he picked up a traditional Japanese knife with a coat of rust for $3 and transformed it into a kitchen worthy chopper while Kohaku the cat supervised.
-Via Laughing Squid