[TommyW]

Simple, dumb and hence incredibly well suited to my brain....highlighting.

Smart, useful and fun would be wiki-style links, either to subsections or other docs or actual lines....

Ditto to the column hiding.

Ditto to the search pane (love VoodooPads...)

Smart Folders sounds like it's great, but I don't really use OOP as an Info Gathering type tool. It excels at making documents I think. But it might be a nice option....