So here's what ya do. Buy some dry ice (wherever possible.) Then either find or get an empty PLASTIC bottle with the cap still there and intact. Then pour water into the bottle (the more you put in the less time you have to run), put cubes of ice in (the more you put in the less time you have and the larger the explosion), twist on cap TIGHTLY and throw immediately. Can work in any time frame from 30 sec. to 2 min., and is incredibly loud. The reason you must do it in a plastic bottle is so that glass shrapnel doesn't go anywhere and kill people.
Here's how it works:
Dry ice is so cold that it goes from a solid to a gas, skipping the liquid phase. Since gas is less dense, it will expand ALOT and will eventually explode. I have never tried it without water, but it probably would either take to long or not work
Instead of lighting off fireworks and possibly blowing your hand off, use a dry ice bomb instead.