I was tempted to have a play with this sort of thing when I saw what the commercial 3D printers were achieving. I was put off by the very limited capabilities of the cheap DIY solutions I was considering: single colour, no filler, relatively poor resolution and hence poor surface finish. The technology seems to be coming on in leaps and bounds and I've no doubt that sometime soon they will be as cheap and accessible as inkjet printers are now, but at the moment the DIY solutions are IMO still not good enough to produce finished goods yet and the commercial printers are a couple of orders of magnitude to expensive for casual use. Commercial printing services still seem like the most sensible option at the moment.