Lucanus cervus (Stag Beetle)... the Jesus beetle
This photo is of a male stag beetle that I pulled out of my friend's pond. Given it's rigidity and complete lack of movement for several hours we assumed it was dead, until it moved. It turned out to be well and truly alive and strated becoming very active. OK, it may not have actually come back from the dead, but it makes a good story.
Incidentally I have pulled many drowned stag beetles from ponds, which isn't good news. However around Windsor they are pretty common (I saw two males in flight on a short walk back from the pub the other day). When I was in primary school we used to collect the dead remains of stag beetles that had become prey to carrion crows.