"Technically, rain that falls on your roof isn't yours for the taking. It's
a resource of the state, which regulates the use of public waters through an
allocation process that can take years to navigate."

http://www.bellinghamherald.com/nort...ry/473205.html

Strangely, I don't think you need a permit to MAKE rain (probably something
to do with Native American religious practices...).