Whitney punch.
 

When I did a/c work I acquired this tool. It's just another way of punching holes in things, but sometimes it is faster than using a drill. I have punched through 1/8 flat steel with mine using a couple of the smallest punches.

I found their web-site and did some reading up on this model, and it seems that maximum rated capacity is 1.2 tons. That’s a hell of a lot of pressure, I didn't figure it was that strong. You can also order a variety of different punch shapes as well.

I don't know how many of you would want something like this, but I figured I would post it.

LINK___ http://roperwhitney.com/punching/2-45.cfm

I have that also. I use it mainly to punch 5/16"/8mm holes on Body panels like 1/4 panels, roofs, etc. when replacing them on collision repair vehicles, Prior to fitment & welding.
Very convenient tool to have.