Simulating VHDL of an AVR8 soft processor (http://http://hackaday.com/2011/04/07/simulating-vhdl-of-an-avr8-soft-processor/)
http://www.ece.uah.edu/~lacasa/pic18/pic.html (http://www.ece.uah.edu/~lacasa/pic18/pic.html) Building a PIC18C and System-on-a-Chip in an FPGA
PIC18 VHDL Source (http://http://www.ece.uah.edu/~lacasa/pic18/pic.zip)