Bristol:
About
Oftentimes, when inputting text on a computer, it is often desirable to insert free hand diagrams or illustrations. A more complete solution would integrate more tightly with the text, however, in order to maximise the number of cases in which it is useful, Bristol is designed with current operating system paradigms in mind. Bristol is a background process with a system tray icon. At the press of a hotkey, it summons a blank window on which the user can draw. When the window is closed, the image is immediately copied to the clipboard, ready to be inserted wherever it is needed. This is useful when explaining something via online messages, or to insert ad-hoc illustrations into informal documents.
The source code is available here.