Time to replace every single window in the house.
Made by attaching 5800 mirrors to an old satellite dish, it focuses 5000 times the heat of the sun to a 1 cm point, obliterating virtually anything in its path.
Someone blows up a lake and causes a homemade tsunami. Check out that wave.
Some kids make a pretty cool waterslide off their roof.
A cool video clip of a homemade tank. You will want one after seeing this video clip.