> I've inspected the ones on my trampoline (where they're easy to see, because the tramp's black) and I have found them to be poor little insects of many types, some dead, others feebly crawling about, with many soft white threads bursting out of their abdomen.
>
> I'm guessing that it is some sort of predatory fungus that eats the bug's insides, but I'm not sure. Can anybody help me identify what is causing this wanton slaughter?

This sounds almost exactly, but not quite, like baby spiders on the move.

I know that some spider babies, when they're leaving home, climb to some high spot and shoot a small cloud of thread up in the air, which is then caught by the wind, thus carrying the spiders to new and less crowded land.

But you say there are several types, and the threads are bursting out of their abdomen. Not their end (butt), but their stomach? And the fact that they're mostly dead doesn't fit, either.

Trav"have no clue"holt.