Some of you may have a pen tablet to use with your PC....such as a Wacom....usually used for painting or freehand drawing...typically Corel Painter or Photoshop; but it works with all programs that use a cursor....as a "pencil" alternative to a mouse....even includes an eraser if you flip the "pencil" over.
So I recently got a Wacom Intuos 5 tablet. It also has programmable keys, a rotating "wheel" for pan/zoom/brush size etc, and the tablet works like an iPad for finger gestures (also programmable).
I'm now using it with TFP and love it. For example made one key do alt+t=m for instant measure tool. Also for pan and settings etc. Will add more as I proceed.
The Wacom can be setup different for each program (keys setup different for each app); and for "all" (for general windows use)...it changes automatically and resting a finger brings up a temp display for every key name. Also has a "pie" wheel where each pie segment has a "key" function (user changeable) for ease of use with pen or mouse.
Telling you all this because if you already have a Wacom, try it with TFP. If not and you have use in several programs it may be worth the cost. There are several cheaper knock-offs but Wacom is the de facto industry std. small/med/large sizes and more
See it at http://www.wacom.com/