Take a look on Greg Egan's short stories.

Axiomatic (LEARNING TO BE ME - Crystalline minds may take the place of human brains, but where does the self really lie? CLOSER - Lovers exchange bodies and minds,but their experiments go just that little bit too far, proving that you can have too much of a good thing)

Oceanic ("Greg Egan again shares his vision of how extreme future technology could be used by future societies to learn that ever more mysteries await our understanding.")