Quantity   Component name
1 × TP4056 USB charging board Lithium ion/polymer charging board. dirt cheap on eBay, especially in multiples.
1 × XL6009 buck/boost converter DC->DC buck/boost converter. Any boost converter capable of stepping from li-ion voltages (3.7-4.2) up to the requisite 5V will work so long as it fits in the handle.
1 × Arduino Pro Mini 3.3v (Atmega 328p)
1 × MPU6050 accelerometer 6 Degrees of Freedom accelerometer/gyroscope
1 × 18650 Lithium Ion cell
1 × Optional: Pololu Mini Pushbutton Power Switch (version SV) https://www.pololu.com/product/2809 Not strictly required, as you can get away with a slide switch, but a planned upgrade will make use of it.
1 × Optional: USB-A Female socket this can be skipped if don't want to power external devices.
1 × WS2812B "neopixel" led strip 144 leds/meter density
1 × 1000 uF capacitor
1 × 470 ohm resistor
1 × Optional: Male/Female headers I built in several wire disconnects out of headers to make simplify replacement and debugging of some components. If you want to solder everything, go nuts.