Adafruit’s Bluefruit devices are hands-down the easiest way to get Arduino communicating over Bluetooth. Taking inspiration from the helical Guggenheim museum, this project coils a contiguous reel of NeoPixels around a dapper top hat to create a wearable scrolling message display you can control with your iOS/Android phone or tablet.
If you're here, it's because you want to learn how to build and make stuff with electronics! And, you're in luck: there's never been a better time. Gone are the days where you need thousands of dollars of equipment and lots physics/math background. Nowadays, if you want to learn to work with electronics, you can jump right in for $20 or less, and any sort of computer.
Pokemon GO has shown us that people can really go crazy over running around our cities bent on catching imaginary animals. It has also shown us that people are going crazy over chasing down said animals at all hours of the night and not always paying attention to what is going on around them. This is amplified when we are talking about children that are having a blast literally trying to catch them all. Build a safety light that's also a lovely way to show team spirit with this no-solder project!