The Woman in the Dunes

I enjoyed The Woman in the Dunes as well. Very well written, though it left me feeling a bit disturbed. Another great novel (also Japanese) is Kokoro by Natsume Soseki. It's not sci-fi and the plot isn't especially thick, however just like a lot of Japanese novels, the focus is on the character development, and it is done very very well.

I think Haruki Murakami (http://en.wikipedia.org/wiki/Haruki_murakami) is one of the most interesting and weird contemporary novelists alive today. On a similar Japanese tip, also check out anything by Kobo Abe, particularly The Woman in the Dunes and The Box Man. If you're into sci-fi, as inevitably a lot of hackers are, Jeff Noon's Vurt and Pollen are both brilliant.