DOCTOR WHO did a really nice nod to CASABLANCA with Mickey Smith and the Cybermen of Paris.

STAR TREK did a really lousy nod to GUNFIGHT AT THE O.K. CORRAL.

(And their version of The Pueblo Incident was just a tad too timely, IMHO).
"Good night, Dr. Carruthers." "Goood - Bye, Roy................."