[danbmil99]

I would suggest reading "The Futurological Congress", compare and contrast to Dick's "Time Out Of Joint". It's pretty clear Dick was a big influence on Lem's later work.

"Return From The Stars" is also pretty good as I recall. Not a big fan of his early Tichy stuff though (it suffers from his own "Agatha Christie" kind of mediocrity IMSHO).

Of course, Solaris is considered his masterwork, for good reason.

[edit] Also, "A Perfect Vacuum" is a one-of-a-kind treat. And now that I'm thinking about it, "His Master's Voice" does "Contact" one better. (in fact it seems like Contact may have ripped Lem off pretty hard...)

[edit2] Damn, he did write a lot of good stuff. The short story "Non Serviam" presaged the Matrix and Greg Egan's Permutation City.