I was looking at a card shuffling machine, battery powered, in a catalog. I'm sure you've seen the ads for these. I never actually saw a real one...just the pictures in catalogs.
But, today, I found myself wondering if, being mechanical, that they in fact do a perfect shuffle, a butt shuffle, or we say Faro shuffle. I'm not saying I know the answer, but I never even heard it speculated about.
But, if it does do a "perfect butt shuffle" or Faro, think of the patter possibilities. As you talk about how the use of the shuffling machine precludes any "hanky panky" on your part...while really you could be doing a trick based on Faro shuffles.
I don't want to buy one based on the hunch that this may work...but if anyone out there has one...try squaring up the two half-decks very well and maybe have one face up and one face down as a way of testing my hypothesis. Either the cards come out alternating face up and face down - or NOT.
Regards, Gregg Webb

That is a very interesting question.
If the machine does a perfect Faro then one would need to run the cards through the machine 8 times to return to initial order.
I think that may convince the audience the cards were really shuffled good but that is a lot of dead time running them through.

Those machines generally do not achieve perfect shuffles. As for running cards through eight times... there is so much you can do with just one or two faros. By the way, the majority of those cheaper machines shuffle the cards in such a way as to result in being a clumpy riffle shuffle. If the machine has two bays in which you must put about half the deck prior to the shuffle, then that means you can control the cut before the "riffle". This would allow for a lot of seemingly hands off gilbreath applications. These machines can be found rather cheap and may be a fun toy to tinker with as far as the ideas I mentioned go... but to my mind, as soon as you take out a "machine" it is subject to suspicion as a magicians prop... you would need a very entertaining presentation to justify it's presence and to compensate for the "heat" due to you supplying your own shuffler. Still, as I said they can be found very cheap so... Good luck.

I thought of this a few years ago and asked Vanishing Inc if it was possible. If I remember correctly they said it's been tried in the past but to no avail

There are machines available which do what you might want. See certain "gambling" houses.

What about a magic tool maker constructing a Magician-Shuffling-Machine? Endless possibilities... Faros, Falseshuffles, Deck Switch...

They already exist. Seek and ye shall find.