True mind fucks, singularity/quantum mechanics:
Permutation City, Planck Drive, etc by Greg Egan
Accelerando by Charles Stross
Favorite example of capitalism/economics in Sci-Fi:
First Contract by Greg Costikyan
Exo-Skeleton/human enhancement:
Armor by John Steakley *** Amazing psychologically ***
Starship Troopers by Robert Heinlein
Some cool nomadic/social technology ideas I liked:
Distraction by Bruce Sterling
Heavy Weather by Bruce Sterling
Scariest First Contact:
Blindsight by Peter Watts
Superhuman, central figure that changed history:
Childe Cycle series by Gordon Dickson
Dune series by Frank Herbert
Ender’s Game by Orson Scott Card
Distancing effect of time-dilation effects from space travel:
The Forever War series by Joe Haldeman
This is just a bare fraction of the scifi I have read and enjoyed.