These people don't care what realdave can see.<quoted text>
I don't get all the excitement.
If you look at an older plotter where a stylus deposited ink in two dimensions based on computer controls. Add height & have your stylus deposit a composite material instead of ink.
You have to have a program for every part perhaps generated by a cad system.
I can see the use in industry to produce parts that do not have huge quantity demands as I would think injection molding would be cheaper.
As for home use, other than perhaps for an artist or a craft application, I don't see it.
Its like a potter's wheel, unless you love to do it or sell your pieces at the local festivals, there are only so many pots & vases you need.