We have a ton of mice on the farm. I haven't gotten around to it yet, but I was going to construct the "ultimate electric bucket mouse trap".
Pick your location based off of rodent activity. Bury the 5 gallon bucket up to the PVC pipe (so the pvc pipe is resting on the ground and acts like a tunnel into the bucket for the mice) and bait the bait cage (made out of hardware cloth) with your favorite mouse attractant such as peanut butter mixed with feed seed).
Run the hot wire (the sheathed hot wire for electric fences, not the bare hot wire) off of an electrical fence energizer and then at each bucket location have some type of tie-in for the sheathed wires coming off of the bucket. I am simply going to strip a section of the hot wire off of the fence energizer at each bucket location and use a heavy-duty copper alligator clip for the hot wire and ground connection. I am going to used the sheathed wire for the leads off of the bucket as well.
To check the trap, turn off the energizer, un-clip the alligator clips, remove the bucket from the ground (the hole should be molded around the bucket and remain intact), pry off the lid, and remove the deceased mice from the water with an old set of BBQ tongs or just pour out the water making sure it doesn't get the interior components wet. The mice will either die instantly, or drown.
Replace the water if needed, replace the lid, and re-seat the bucket. Reconnect the wires and turn the fence energizer back on. Should be able to hold many, many mice if you only check once a week.
The only concern I see is if a snake decides to go into the tunnel. It will either get fried as well, or end up in the water. So be careful removing the lid!!!
I take no responsibility if anyone builds this as it is an idea from a bored hillbilly and probably does not meet ANY safety codes.