Need more buttons

I need something like the logitech g13 for more buttons but it's too expensive, i just need something like a basic external numpad. would it be possible to edit drivers on a external numpad for more buttons?

found this so it looks like it might be possible

http://stackoverflow.com/questions/6530501/how-to-edit-a-device-driver-file-sys

http://www.amazon.com/XK-24-USB-Programmable-Keypad-Windows/dp/B003MB780E

http://www.cherrycorp.com/english/keyboards/Office/Slim_Line_Prg_Kypd/index.htm

the top one is way nice but a little expensive but, yes you can mod the key map on a "human input device".  honestly any keypad or number pad will do but the button pictures wont corispond....thats why the top one is cool...

 

hope this helped

get the cherry one