Here is an intersting scoop.
ScanR is offering a service where you could email them a picture of document etc. taken from your camera phone and they would clean it up and send it back to you as a PDF.
Right now you can try it for Free
Whats even more neat is that they have software for the Window Mobile 5.0 that makes it even easier.
I have no idea about the quality or the cost of the service when they start charging. Those 2 obviouslly will be big considerations to weigh in contrast to the burden of borrowing the document and scanning it yourself and what not.