list.it, or the Latitudinal Information Scrap Trapper that Indexes Things, is a small, simple note-keeping Firefox extension designed by MIT researchers to help you manage the tons of little information bits you need to keep track of each day.
To start using it, you either click on the yellow note icon or press the Ctrl+Shift+I key combination to get this non-intrusive prompt.
The list.it dashboard is located in the sidebar, and can be accessed by pressing the Ctrl+Shift+F combination. You can also search for text in the notes, or delete old notes.
A neat feature with list.it is the ability to synchronize / backup notes. So in case you are using multiple machines, you can still have access to the same set of notes.