Chrome: Sometimes when you’re working, you need to jot down a quick thought. Instead of opening an app or another browser window, Sidenotes lets you create a note in your current window. Those notes then sync to Dropbox.
The extension puts an icon near the address bar. To start taking notes, click on that icon or press Ctrl+N. The note gets associated with the web site you’re viewing. If you return to that site later, the same Sidenote comes up. The extension also lets you view all your notes at once and search within them.
Google Keep performs a similar function, but this is a no-frills alternative that keeps the files in your Dropbox.