Fidget spinners are a thing these days. We have already covered a bunch of unique ones already. The 8Mode LED Fidget Spinner is also worth a look. It comes with a spinning LED display that shows RPM, spin time, and other info in real-time. Simply press the button to select the appropriate mode and spin.
The 8Mode spinner can show time, text, count, and cool effects. It was made using a microprocessor, spin sensor, 2032 batteries, and a few other simple components. Expected to ship in October.