I had recently made a post on the suggestion forum that was to suggest a way to "zap" players/mobs with a floor tile. I wanted the tile to be energized so that if you walk on it you get zapped! I mostly wanted it for cooking some creepers who liked to loiter around my front door. Through trial and error I've found some interesting stuff:
To make such a contraption with the current items and blocks you need something like this:
Power In -->
where = RS switch = exposed wire
sort of a feedback loop that sends MV current in the middle. The exposed wire will energize all adjacent blocks like this:
MinecraftNotch.png" wcf_src=http://forum.industrial-craft.net/wcf/images/smilies/MinecraftNotch.png alt="MinecraftNotch"> <-- not zapped.
where is an energized block.
The only problem is that it will not zap players/mobs standing on top of a . Therefore, it is necessary to make those top blocks half-blocks of some kind. Then if the RS switch is off, current will flow and anything standing on one of the half-blocks will get zapped!