Interesting thread, gents. As a working industrial and graphic designer, this is a subject that I get to deal with intimately every day.
An interesting item that happened to me recently involved a railroad museum. I discovered that their policy concerning work done for use by them assumed that they owned all rights to the work although no compensation would be offered and no agreements would be signed. This policy was also not stated when work was done. I pointed out that their policy was contradictory to law and would need to be revised. Potential for some big problems there, as someone pointed out. The expense of violating this one is huge.
A related issue they had concerned a member who began copyrighting museum publications he was doing for them in the name of his own private company and copyrighting the photos and graphics from their own collection for himself. They may have lost a lot by not being saavy to the laws.