I've looked into this because we had a coyote "problem" in our old neighborhood in California. It was a problem because the coyotes, whose natural habitat is being destroyed by new housing developments, began to come into the neighborhood at night and steal the pet cats.
It was very strange because the neighborhood was not rural in nature - it was a dense, tract-home neighborhood typical of California.
Although coyotes should not attack adult humans (unless rabid or otherwise sick, as noted before), they will attack and kill small animals like cats and even small dogs � for food. Coyotes have also been found to "pack up" at times to attack larger animals, like sheep.
So, I would recommend that if you have small animals, you might want to keep them inside the house or under close supervision outside if you know you have coyotes nearby.
If they start to come into your yard during the day, or something strange like that, you can probably call an agency like the Fish and Game department (depending on what they have in your state), and perhaps they could relocate them, or at least check to make sure they're not sick.
I have to share one story I heard that is so bizarre to me . . . It was told by a coyote expert on his website. Supposedly a woman found a stray dog at the side of the road and took him home to join her other numerous dogs. (I think she had at least four, heaven help her). The stray got along great with all the other dogs and all humans. But the first time they took it to the vet, the vet freaked out and said it wasn't a dog - it was a coyote!
Apparently the vet told her not to let too many people see the "dog," because it could be taken away from her because it was a wild animal.
Anyway, I guess it goes to show they can be very nice, too!