YouTuber Daddy Handy's channel is, understandably, about a handy father and the various DIY projects that he creates. He's got a couple of videos up, including another one on building a solar powered playhouse but his most popular video is definitely this one, which shows a DIY go kart that he made using parts found in any decent hardware store and some household items. While the ingenuity of building a working kart in general is already mind-boggling for someone as un-handy as myself, what really has people talking is the power source for it.
This kart is motorized, using a handheld drill as the engine that powers the rear wheel. A length of cord wrapped around the trigger and attached to the accelerator pedals quickly turns the drill on and off for the desired amount of speed. It should be noted though that this kind of design is only good for a smaller child. Older children and adults will weigh more than the drill could safely push so you may have to modify the design and/or add more drills if you want to take it for a spin yourself.