To make a pain bomb you simply need a metal pain can with a refastenable lid, a nice bright color paint (green, pink, purple, or some gross color is perfect!), and a quantity of dry ice. Place the paint in the can and then drop the dry ice in. Quickly place the top on and then run like hell!
With some testing you can time this to a science. It depends on the ratio of dry ice to paint to the size of the can to how full it is. If you are really pissed off at someone, you could place it on their doorstep, knock on the door, and then run!! Paint will fly all over the place!!