Here is a cool longboard with LED strips that react to your speed, allowing you to put on a better show at night. As nusnel explains, you can build your own by adding programmable LED strips to your longboard. You are going to need 2 Arduino Micro units, a Hall Effect Sensor, 1 x power bank, and a few other parts to get started.
You are also going to need a soldering iron, hot glue gun, and other simple tools. More information is available on instructables.