Those are really cool. A few companies use them for producing hobby items already, but the technology is nowhere near perfect and the cost of the machine and product is still quite high. I don't know if they are still around, but Print-A-Part would print out parts to your supplied specs. Fine Scale Modeler featured them in an article quite a few years back now. The new defunct Hard Corps Models used lithographic printing to offer some sets of printed resin, workable tank tracks. Downside was fragility, pebbly surface texture and cost. At $100 a set they cost twice as much or more than alternative track sets in plastic or metal. There is an outfit now selling a 1/72 civilian light plane kit. Its pretty nice but again has a rough texture that needs to be sanded down, and is over $100 for a four inch long plane that would cost $8 in plastic.
My last contract job was painting small (maybe 1/6 scale) Apple II computer replicas. They had been made in top and bottom snap-fit halves, to serve as vanity covers for flash drives. The layering process was evident in the parts, but it's hard to quibble when you find perfectly realized keyboard buttons and tiny air vents made with absolutley no flash whatsoever.
The technology is prohibitively expensive and the resulting parts have textural issues now - but injection-molded kits weren't so hot at first, either. The 3-D printing process strikes me as being simply the next phase in the evolution of our hobby. It's going to be interesting to see where this new process leads!
That video is essentially the 'Chinese knock-off' of the makerbot/reprap. (Nothing against the Chinese!) It's a more elegant and striped-down design.
Makerbot, I've got their discontinued 'cupcake' 3d printer, rather than going cheaper is making bigger models for bigger money. The cupcake was ~$1k a couple years ago and their cheapest model is ~$1.5k nowadays. I think that printer in the video was a similar price, as of a year or so ago.
You can build a reprap yourself for hundreds of dollars if you are inclined to do so and once you have it at a 'bootstrap' level, it can build the rest of itself, itself. Nice! The plans, even for the makerbots, are public domain. The biggest cost is in the electronics.
The biggest downside is that this tech is still in the hobbyist phase and not ready for prime time. If you have a problem, you are fixing it yourself. But with makerbot/reprap, there is a big community out there to help. I'm ditching a makerbot 'party' this afternoon to get some other projects done...
Some printers run smooth, some are wonky. All require a lot of TLC and hand tweaking. That has been the downfall for me. I don't have the time to truly sit down and tweak the hundreds of settings in the software to get a perfect print each and every time. A print can go for hours and then in the end phase, the smallest glitch can destroy all those hours of work. In that regard it's much like the 1st gen of 1x cd burners from nearly 15yrs ago. 5 mins left on a 1hr burn and, oops, buffer under run and you've got a drink coaster. With 3d prints, the bad ones are less useful than a coaster.
It does prove that the tech is getting there though. If you have another decade to wait, then 3d will be much more ubiquitous. If you have over a grand and lots of time on your hands, then jump in now, the water is nice once you get used to it.
These printers drip plastic in small lines on top of each other. Essentially, you get a striated print which is true of even some of the $20k printers, (but not all). This is the resolution, as it were, which is only as good as the size of the extrusion nozzle. The cupcake is somewhere in the 2-5mm range (3mm avg) depending on how fine you get your settings on a per-print basis. The next step-up for makerbot narrows the range. The repraps are similar. The printer in the video, I don't know the resolution.
With printing ABS, you can smooth that texture with a quick wash in acetone to melt the exterior. Some sanding and standard model finishing techniques bring you the rest of the way home.
But if you anyone expects perfection or near-perfection out of the gate, don't bother. Wait for many years, or dump $20k+ on a good printer now.
And these DIY printers aren't limited to ABS. They can do one or two other plastics and basically any semi-liquid that can be pumped through the nozzle. The 'cupcake' was so-named not only as it can make a part about as big as a cupcake, but can also print chocolate frosting or choco 'candies'/cookies.
Here's my cupcake printing a Tardis and ruining an hour's worth of printing just shy of the finish line. For ref, it's not much more than an inch wide.
Slips at the 6 min mark.
And here's the printing finishing it's ruined state. I could have stopped it, but this late in the game I wanted to see how it finished off.
There are ways to improve the resolution you see in this video on this build, but I wanted to see how well it did without tweaks.