>A black hole is machinery?

As far as I can tell.

>That's a big machine.

Well, they do end up infinitely small you know!

>This is true, but to be truely invisible it would have to also not block light coming from what's on the oposite side of the observer.

Right-O.

>But, if that did exist and that technology was used in my new big black hole machine. I'd finally be able to show it to everybody.

At this rate, we will have a Douglas Adams tribute on our hands fairly soon.