There are quite a few options to protect selected bookmarks from being accessible by other computer users. It is for instance possible to use a bookmarking service, use deeply nested bookmark folders or a start page service to list the bookmarks that other users should not see. The options have in common that they hide the links but do not protect them once the page they are hidden on has been found.
Link Password offers an interesting alternative. The experimental Firefox add-on can encrypt links in the web browser so that their original destination cannot be seen or guessed by looking at the bookmark.
The Firefox add-on will encrypt links with the AES encryption algorithm which means that users have to enter a password for that link to encrypt and decrypt it. It is currently only possible to encrypt one link at a time by selecting the “Make new Encrypt Link” from the Firefox Tool’s menu.

Encrypted links use the newly defined cryptlink:// protocol. The add-on will automatically ask for a password when the cryptlink link is opened in the web browser. These protected links can be bookmarked.

An option to convert existing bookmarks into protected bookmarks would be nice. As would be the ability to protect multiple bookmarks with one password to use all of them normally once the password to decrypt them has been supplied by the Firefox user.
Link Password offers an interesting option for users who want to protect bookmarks in the Firefox web browser. It can be downloaded from the Mozilla add-on repository.
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Returns “Corrupted Link”…
You can install it by clicking on View All Versions at the bottom.
Works! Many Thanx!
Total downloads for this add-on: 10
must be brand new!
Hello.
Fun and see that I have a few of my users plug into.
I have noticed era idea and will check on it as soon as I get time. But worth mentioning is that and this is my first plug in for firefox and I still can not quite how the APIs work against firefox.
Regarding a comment so I added it up 2010-05-14.
/ Evighetens Filosofi
Hi I have a new release version of Link, Password,
And it added that it can encrypt the existing links and folders, and right-click the folder / link.
I also like to take in the more suggestions on what to develop in this plugs into.
https://addons.mozilla.org/en-US/firefox/addon/161768/
/ Evighetens Filosofi