Here's another one, my personal favorite:
We by Yevgeny Zamyatin, written 1920-1921.
http://www.amazon.com/exec/obidos/ISBN=0380633132/forkrecommendedrA/
This novel criticizes Leninism, much like Orwell's 1984 criticizes Stalinism.
It reads like a mixture of 1984 and Brave New World. In fact, both were
influenced by this novel.
-JoeF