Ever thought about running a headless AutoCAD session? do you do a lot of script processing? then see:
Bascially anything you can do at the command line you can do with a new AutoCAD Core executable - inlcuding running LISP, Scripts, plotting, objectDBX, etc. If you can drive it without having to see the graphical entities, you can do it with Core and omit all the overhead the GUI takes up.