A tip I've discovered to make the most of your Links Bar space: It works with both IE 5.5 and 6.0, athough I haven't tested it on earlier versions. If you drag a subfolder of your Favorites into the adjoining Links subfolder, that folder then appears on the Links bar as a neat little drop-down menu, complete with fly-out submenus. I now have most of my Links bar populated with folders, and find it makes navigating bookmarks much easier. I haven't seen this documented elsewhere, so just thought I'd pass it on.
Andrew Denny
Norfolk, England