DolphinSearch, distributed by Reed Elsevier and now in use in the Enron case, is a litigation tool that uses artificial intelligence to analyze language and retrieve hard-to-find documents.
Recite is one of the more innovative things to come out of Microsoft's Windows Mobile team in the past few years, a voice-based note-taking tool that gave users a quick way to say whatever was on their mind, archive it, and retrieve it later by speaking any keywords from the recording.