While there are many, many information managers for the Mac, DEVONThink is the only one that claims to have a "powerful artificial intelligence (AI) architecture that helps you organize and navigate your information collection quickly and accurately." Now after an extensive testing period, DEVONtechnologies is officially shipping DEVONthink Professional Office 1.3. The Office version adds scanning and OCR support to DEVONthink, allowing you to scan documents and make them searchable. They note that DEVONthink works particularly well with the Fujitsu SnapScan (right), for getting all that paper into your Mac.
DEVONthink comes in several versions, with Professional Office at $139.95 (though educational discounts are available) and demos are available.