You people who believe in the singularity very obviously don't know how a computer works. It's simply an electric abacus; look at schematics for an ALU or a logic gate. How many beads do I need to put on my abacus before it becomes self-aware?
The danger is anthropomorphism; it's simply too easy to fool people into believing they see sentience where there is none. Evil people will use this to their evil ends.