Its yet another form of Vermicomposting. The insects are voracious eaters, multiply quickly but are harmless. Its the larvae of a wasp-like fly, (no sting) called a Soldier Fly, that do the work. They break down compost very quickly and excess larvae can be fed to chickens as a very nutritious treat (high in protein and calcium), making them multi-purpose. Another good thing about them is that they also consume meat and dairy- something that Red Wigglers cannot do.
They are not expensive to try- i have wanted to try them myself ever since i read about them last fall. This is the most recommended online place that i have found. Phoenixworms.com
A google search for them will show many articles about the specifics. Happy hunting!