Here’s a handheld POV toy packed into an Altoids tin. The brain of this device is a Parallax SX microcontroller, while it’s powered with two AAA batteries. 7 LEDs provide the POV display that is capable of storing 32 messages.
There are 32 message slots — 16 are straight hard coded bitmaps, 16 are text strings of any length. The text strings are mapped to ASCII character bitmaps with one extra trick — the engine will look for a break in the text string (a space character) after a set number of characters, and show JUST THAT PORTION of the string for 4 seconds or so, then it moves on to the next portion of the string.
Via Hacked Gadgets.