Here's something I just thought of. The closed-eye scribble. I like it.
1) Open MS Paint
2) Select the Paintbrush
3) Select circular brushstroke
4) Close eyes
5) Count to 30 seconds, while moving the mouse, left button depressed
6) Open eyes, save scribble
The default canvas size when opening MS Paint takes up less than 25% of the screen. So, most of my scribbling won't actually be recorded at all. This makes the creation of each scribble very random and enjoyable and wonderful.
FIRST CLOSED-EYE SCRIBBLE