Behold...
...the Lego Basket Shooter module, from general-purpose Lego-Technic demigod "Akiyuky", whose Japanese blog is here.
Each of the three shooters has individually controllable aim and power, which is what makes the machine's nigh-miraculous accuracy possible.
Via TechnicBricks, here's how it works.
The shooter is meant to work as a Great Ball Contraption module (previously), accepting balls from an input, doing its thing with them, and then delivering them to an output. Only the (surprisingly large percentage of) balls that go through the basket go to the output.
Here's a Contraption composed of 17 of Akiyuky's modules.
18 September 2012 at 1:20 pm
Mouth: agape. That's about all I can say to that.
Well, that, and the envy welling up inside me--I wish my collection were so impressive!
18 September 2012 at 9:05 pm
My god. Does Matthias Wandel know about this?
19 September 2012 at 9:24 am
I played with plain ole Lego as a kid. This is calling me like a siren. Can I buy these things as kits with instructions?
19 September 2012 at 1:55 pm
A few people have made instructions for making GBC modules - see here, for instance - and detailed pictures of them, as in the above videos, are often adequate. The basket-shooter mechanisms aren't actually all that complex. I don't think anybody's ever sold GBC modules as kits, though.
Getting the pieces to make specialised Technic contraptions like these would be a serious pain if you had to buy whole sets that contained them. The basket-shooter, for instance, has several linear actuators in it; you'd have to buy a few excavators to get that many. Fortunately, you can buy individual pieces direct from the manufacturer, and also on eBay and BrickLink. BrickLink can be surprisingly cheap, too, even if you're buying brand new pieces.
The last part of the puzzle is knowing exactly which piece you're looking at. Taking the basket-shooters as an example again, they use shock-absorber springs, but there have been umpteen different kinds of Technic shock absorber over the years. You can look up pieces and their exact part numbers, which you can then search for on BrickLink, on Peeron.