Instead of using the trackpad to move the pointer from the location it is currently in, is there a way to use it more like an entire-screen pointer? That is, I touch the middle of the trackpad and it puts the pointer on the middle of the screen? I'm on OS X Lion.
Inklet is what you are looking for. It works like a charm on OSX, but it's a paid application. Well worth the money if you use it.
You can use it full-screen, or assing a region on screen where you want to draw. And if you have a capacitive stylus, you can even use that for sketching or writing.
I never found a Windows counterpart, though. I'd love to use my trackpad as a simulated full-screen touch panel. But never found a way for that...
(I'm not affiliated to Inklet any way.)