CanoScan Toolbox for OS X
I have been using the CanoScan Toolbox software which came with my CanoScan LIDE 500F Scanner. This is a very difficult to use software. It does create PDFs , and will let you customize some scan settings for images if you need. Its very clumsy — you usually end up overwriting your last scanned file — and very confusing to scan to an image file instead of sending an image to a program like IPhoto (hint, don’t scan, save). And woe to you who check the “Confirmation of Exif and Scanned Settings” Box.
Had I known about the quality of the CanoScan Toolbox (at least on OS X), I would have opted for a different brand. The clumsy, time wasting interface is a long way from the Mac experience I would expect.