Back in the day, we would fill them with flammable gas, (not the liquid kind)
attach a few feet of toilet paper, light the paper and let 'em go.
They would phloat phallicly away to ignite at at a hundred feet or so.
This was at a boarding school where one kid was found to have a whole load of them.
He had expectations far beyond the possibilities of the institution and did not need them.
LOL !