this is just a simple flashlight i've created
i printed the case on the back side with support, but you can also print it on the front side.
you will need
6x5mm LEDs (colour of your choice)
1x5Ohm resistor (i'm using 2x10ohm resistors in parallel)
1x18650 lithium ion battery (from old laptop battery)
1xTP4056 lithium ion battery charger
1x switch

hope you like it.