Folder Remarker Description:

Folder Remarker is a shell extension for Explorer that allows you to add
descriptions and notes to your files and folders. Just click right mouse
button to activate context menu for any file or folder and select
"Properties" menu item. The Property sheet now contains a new "Comments"
page where you can add whatever text you want. You can edit the description,
it will be saved when you click "OK" or "Apply" button.