This is a more fun version of a zap electric scooter.
Kind of what Segways would be if they were more dangerous: ie fun.
Step 1: tear your electric zap scooter to pieces.
these things run about $500. i got given one for my birthday and wanted to try something wild. a cheaper way is to buy the 250W motor and battery direct. it'd probably run you $150 and can lead to all types of fun projects.