Well this info is well appreciated. I have wondered for many years what the fuck was attached to the large wolf spider my mom found on our porch. Now I know. Thanks!
Another funny thing: My dad said he saw this old boy take a horse hair and leave it in a jar of water and it would turn into a worm. He tried that and it obviously didn't work. Now if someone found a particularly thick horse hair with a worm imbedded this might explain that as well.
This page has other related video, including one of the worm escaping from a frog which has eaten an infected cricket. Warning: May induce gagging, possibly vomiting.