For cult sci fi classics you can't get much better than "Stars My Destination" by Alfred Bester. Other goodies include Dune (of course), Gateway, and The Forever War.
I also recently read Speaker For The Dead (sequel to Enders Game) and was pleasantly surprised. Possibly better than the original.
A sibling comment mentions Tchaikovsky which I strongly concur with.
> Possibly better than the original.
IIRC this was the first book in the universe that the author wrote, but publishers insisted it was a bit heavy, so he wrote Ender's Game as an easier entry into the universe. On the topic of Ender's universe, the whole Ender's Shadow thread is also a great read. The first book is covering some of the same events but from the perspective of Bean.