This is something I can't really send an all-company e-mail about, unlike when someone finds a set of keys in the parking lot or loses something else.
I would! (well, maybe not all-company, but possibly all-office, and definitely all-project)
But I'm also the person who put photoshopped "Missing!" and "Wanted!" (complete with vital stats: height, weight, model number) when the battery charger for the Wii-motes disappeared. So my professional credibility is already shot.