Last WE I spent few good hours building an Arduino based mini POV.
POV : Persistence of vision is the theory where an afterimage is though to persist for approximately one sixteenth of a second on the retina, and believed to be the explanation for motion perception however, it only explains why the black spaces that come between each real movie frame are not perceived. -wiki
I wanted to build a small POV .. mini mini in size so that it sits unnoticed on my desktop! that why I picked a paper tube with a hight h=4.5cm and a diameter d=2.4cm.
Inside the paper cylinder, you find an Arduino mini with the 10bit Led display soldered directly to its pins , small lipo battery and its USB charging circuit, 3v to 5v DC converter, ON/OFF switch)
After getting the brain of this POV to fit in this tinny space, it was finding the right motor and building the whole system so its stable and does not vibrate allot.
After sometime dealing with the instability of the system i found this "little plastic spring" - i have no idea how you call it - think in usb-speaker and it works great in damping the unwanted vibrations and reducing the wiggling .
Here is a little video showing the first test of the system .. it was programmed to display some arabic word (MAYAR - ميار)