You can make your own persistence of vision or POV toy using 8 LEDs, powered by ATtiny2313 (AVR microcontroller) operating at 2 x AA batteries. This is a tiny toy that fits easily inside your pockets even.
“Most POV toys out there uses the code or program memory to store a pattern or message. This means that the firmware of the microcontroller must be changed for every new pattern. This is a great hassle because you need to revise and recompile the program and load it to the microcontroller using a programmer. It takes too much effort and wastes your time. TinyPOV is different. ”