I hate finding LIVE snakes in electrical gear. Happens a lot in rural areas of the West, I've lost count of how many rattlesnakes I've seen when opening a door for the first time. I am ALWAYS cautious now when I'm out in the boonies.
I got chased down a trail by what I was told was a Cottonmouth when looking at a bad AC unit at my hotel in Florida once (I was dieing of the heat and the hotel maintenance guy was an idiot, I could tell it was just a blown fuse). Opened the switchgear cabinet door and the snake immediately took off after me, or at the very least I made the poor decision of running away in the direction he wanted to go. Either way, nobody thought it was funny at the time, apparently they are very poisonous and aggressive, more so that rattlers.