Let's include in this list any TV shows that lasted no more than two seasons.
Here's what comes to my mind at the moment:
KOLCHAK: NIGHT STALKER (1974, Everyone here should be familiar with this show or hang their head down in shame)
THE OUTER LIMITS (1963, The original series of course)
STINRAY (1986, Crime Drama staring Nick Mancuso)
PLANET OF THE APES (1974, Loosely base on the popular movie)
SOMETHING IS OUT THERE (1988, Sci Fi show with the lovely Maryam d'Ado )