Something that would be useful: a running list of abbreviations and definitions on the side of a document reader. The listing depends on which abbreviations had been used up to that point in the paper -- so they appear and disappear as you go down and up the document. The definitions can be attached to the document as metadata, and that data can be modified by the user through the reader to include their own definitions.

A companion to this is a tool which will give abbreviations, synonyms, and definitions for certain terms on mouse-over.

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