KiwiRail - New Zealand
Here is a video of a video camera that was found in a river. Someone lost it when their raft overturned and it continued to record for many hours as it rolled downstream. It was submerged for 17 months if the time-stamp is correct. The guy who found it edited out most of the "stuck in one place" video. If it's yours, contact him and he will send it back free of charge.
