Simply indispensable

Plugin Notes Plus is a great tool to help yourself (and any other administrators) remember why a particular plugin is installed, how or where it is used, or if there are any things you want to keep an eye on with a plugin. Of course, you could also create a spreadsheet of installed plugins and add notes to it there, but that is much more cumbersome to keep up to date.

Because Plugin Notes Plus adds a column on the Plugins page itself, you can see all the relevant information at a glance. IMHO, this plugin is quite indispensable.