Much like waiters and cooks, IT department guys are not to be trifled with. There are many reasons why, but on the top of the list you will find the Etherkiller.
Simply put, this fairly simple DIY device involving an RJ-45 connector spliced onto a power cord that will obliterate anything with an Ethernet port. Essentially you are running 120 VAC though a cable that likes something in the neighbourhood of 2.2-2.8. From what I understand, the results can be gruesome and spectacular. The instructions on how to make one yourself are in the following link, but you know as well as I do that plugging this thing into your router is not going to be a good idea. [Fiftythree via Boing Boing Gadgets]