Allow all users to attach a note to a page.
Offering all users to attach a note can be very helpful to get private comments from anonymous users, reviewers/moderators, etc. without having to create specialized features for each specific case.
By default, anonymous users may not be given access and once given access, it may require them to enter a simple CAPTCHA code to avoid auto-spam bots.
Making one Sticky Note available on all pages could make it useful as a bookmarking system too.
Offer a filter that takes the original body data and searches for TODO lines. A line that starts with TODO, XXX, or TBD (and other keywords defined by the administrators) can be transformed in a Sticky Note.
Since the list of Sticky Note can be shown to the administrator, it is a way to keep track of things to be reworked or improved on a website. Using various tags we can also create specialized list (i.e. one TODO list, one XXX list, one TBD list, one Anonymous list, one moderator list, etc.)
The implementation of the Sticky Notes can make use of the Comment feature. By tagging the comment with the special Sticky Notes tag, we now know that these special comments are Sticky Notes instead.
Sticky Notes are also assigned a private permissions which prevents most users from being able to see them. One exception being the author of the note should be able to see the note.
The display can then make use of a Sticky Notes like look.
See: Anti-Spam feature
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