Our school's scanner scans everything into pdf, and I quite often need them as a form of picture, so being able to quickly convert them is necessary to me. I just scanned our University of Otago Sheilah Winn Shakespeare Festival poster so that I could pop it into publisher and add the entry details. I started with this:
and converted it so that I'd only need about 20 seconds or so to make this version.
Nifty note: pdf2jpg plants a tree for every 5000 conversions!