I'm doing some research on multicore processors and the challenges involved in writing code for them. I'm trying to find out what the first multicore processor was and when it came out. I'm also wondering which multicore processor was the first one that was used widely used by the general public (i.e., by the general public in desktop/notebook computers). I've tried searching on Google, but I haven't been able to find much.
Also, links to research papers/press releases would be useful.