Favorite forgotten 70's movies

I started watching this New Zealand Sci-fi film about a man who is one of the last members of humanity wandering around cities in the Silent World. What are some of your favorite forgotten 70s movies that you've seen. What caused them to received such little exposure, and do the effects hold up today?

Soylent Green & Omega Man.
Both staring Charlton Heston.

Soylent Green was on tv the other night.
I was surprised that the theme & underlining dark mood still resonated nearly 50 years later.

The Fury.

The Great Texas Dynamite Chase
Corvette Summer
Eat My Dust