Zilog, a semiconductor manufacturer, got its start selling the Z80 microprocessor popular with small-computer manufacturers in the mid '70's. You can read the interesting history of the Z80 on Wikipedia. After several setbacks, the company now concentrates on embedded systems, and its Z8 Encore! microcontrollers in particular.

The somewhat-obscure journal, "CrossTalk, The Journal of Defense Software Engineering," devoted its September/October 2009 issue to resilient software, and engineers or designers involved with embedded systems should read at least the first article, "Considering Software Protection for Embedded Systems." This article covers ways that people can reverse engineer and maliciously attack FPGAs, although the techniques also apply to microcontrollers with internal flash memory. And it suggest ways to protect your intellectual property.