Paprika, by Yasutaka Tsutsui

This is also exciting: Made it into an incredible animated feature by Satoshi Kon in 2006 that I longed to read the original of, Paprika, the surrealist dream/detective novel By Yasutaka Tsutsui, is finally being released in English translation!

"The setting is Tokyo's Institute for Psychiatric Research. Major breakthroughs are taking place, using new machines which access the minds of sleeping patients. A couple of top psychoanalysts are in line for the Nobel Prize for this revolutionary innovation. One is the young and beautiful Atsuko Chiba, who uses the equipment at night to cure some of Tokyo's leading citizens of mental trauma. Atsuko has to be discreet because there are strict restrictions upon the machines, so she disguises herself as an alter ego – the eponymous Paprika. Unfortunately, back at the Institute the machines are being misused by her enemies on the staff, and the most powerful versions have gone missing."

[Edit: Of course it only seems to be available in the UK so far, and they won't ship stateside...]