Definitely could be useful.
However, i have thousands of text files I access on 20+ PCs and tablets. One is called xenforo.ideas.txt.
I can pull it up in less than 2 seconds.
I sync all the PCs with dropbox.com
I would like to be able to add a post to "My Favorites".
ZetaBoards used this back when I had a forum there (IPB too, I think), and it was pretty useful for me to take my own personal notes without having to do anything weird like sending a message to myself. I'd love to see this here too.