I have never come across a raccoon or squirrel, but I did find (during a major remodeling) two birds which had become trapped and dessicated behind tar paper covering the inside walls of a friend's garage.  At some point during the construction process, a young hawk apparently chased a flicker behind the tar paper, down between two studs--and neither one was able to negotiate the way up and out. They were still intact twenty-odd years after the fact, but their feathers were really ruffled, to say the least!

Another friend (?) gave me a "mummified" rat which, after eating poisoned bait, fell into an open bag of cat litter and spent at least one summer there.

Catherine B. Parker
Faunal Analyst
University of West Florida