This is the javascript simulator from the visual5602.org project:
www.visual6502.org/JSSim

It includes a general purpose transistor-level simulator, layout browser,
and the data from a 6502 revD chip. 

Recently added: polygon data for the 6800 chip. The simulation is not yet working,

Note the various licenses and Copyright associated with each file.

Enjoy!
- The Visual 6502 Team