Mine comes from the greatest space opera ever written: E.E. "Doc" Smith's Lensman saga. Star Wars, Star Trek, Babylon 5, Andromeda... they ALL owe a source-debt of gratitude to Doc Smith.
If you pick them up today, don't expect great writing, in-depth characterizations, or hard science. Do expect lantern-jawed heroes, incredible space battles, far-out aliens, and trans-dimensional warfare that spans the existence of time and space. !!!!
(Did I mention using the Sun as a ray gun? Or smashing planets together as a weapon? Telepathy? Elder races that control the fate of the universe?)