Simulpic 2.0 is a PIC 16F84 Simulator.
it is free and open-sourced and is a part of the GNU Debian Linux. the significance of Simulpic lies in its simplicity: the system is easy to understand, use and modify. i built a distributed embedded system simulator that is composed of thousands of 16F84's and i found Simulpic to be amenable to hacking. you might find it useful as a stand-alone simulator and/or as a building block for more complex systems.