Another vote for Vuescan - outstanding product. sensible pricing. sensible licencing.
Cross platfrom and works better than most official scanner software.
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"VueScan supports more than 2100 different scanners on Windows, 1800 scanners on Mac OS X and 1600 scanners on Linux. These scanners are organized by vendor name below.
IF your scanner isn't on this list, VueScan may still work with your scanner if you can find a WIA driver (Windows) or an Image Capture driver (Mac OS X) on the scanner manufacturer's web site."