None of these are straight out bookmark/favorites organizers but they assist me somewhat in the task.
Faview--- http://www.nirsoft.net/utils/faview.html This program allows me to choose the firefox bookmarks that I want to export instead of having to export them all. I In effect, it allowed me to choose and organize my most favorite bookmarks onto one page. I export mine into an html file, then open it in a web editor and gussy it up as the export file isn't too pretty. I then bookmark the edited page. It helps me visually to see groups of bookmarks on a page (as if I were viewing groups of links on someone's website) instead of in a drop down folder in my bookmarks. I also use it to export out certain groups of bookmarks that I want to keep a record of but don't want to keep in my Bookmarks anymore. Faview is a standalone program and works with IE Favorites or Firefox Bookmarks. It's not perfect but it's the only thing I found that let me choose the bookmarks I wanted to export. If anyone knows of another program that performs that function, could you post it here?
I love the Bookmark Duplicate Detector listed above, it has saved me from putting so many duplicate bookmarks into my firefox Bookmarks as it lets me know that the bookmark is a duplicate when I am trying to add it.
Another one that assists somewhat in my organization is PlainOldFavorites addon for firefox. https://addons.mozilla.org/en-US/firefox/addon/668 It adds a 'Favorites' menu to firefox where you can directly view all your favorites in IE without opening it up (and also, when using with Bookmark Duplicate Detector, it keeps me from adding the same bookmark to IE and firefox which I was prone to do.) I mostly use firefox but I still often run across pages and forms that won't work correctly in firefox and I have to view in IE. Instead of having to open up IE and copy/paste the URL right then and there, I can add it to the 'Favorites' menu (which is located right next to 'Bookmarks' on my firefox menu bar). Then, when I get a chance to go to IE, it's right there on the 'Favorites' menu in IE also.
If you are a frequent user of google's services, there is a firefox add-on menu button called Gbutts that lists all the links to google's services in a drop down menu outside of the Bookmarks folder. https://addons.mozilla.org/en-US/firefox/addon/3576 That keeps me from having to dig through my Bookmarks folders to get to any google page I'd like, and settings in Gbutts allow you to choose which google links you'd like displayed and how you'd like them displayed. Of course, you might not need this if you use google's toolbar.
For those that like visual organization, there's speedial addon https://addons.mozilla.org/en-US/firefox/addon/5721 which puts previews/thumbnails of your favorites on one page. I didn't care too much for it myself though I thought I would, but others might like it.
