Last year I backed the iBox printer project on Kickstarter. It is a tiny 3D printer that uses UV light to solidify resin. It's a more precise way of printing than my Ultimaker, which is why I fancied having a go with it. Normally light powered printers like this are powered by video projectors and have highly expensive optics in them.
The iBox printer uses a bunch of ultra-violet leds and a small high resolution LCD panel to control which bits get printed. It can only print small objects (around the size of a chess piece) but since the resin is kind of expensive I don't really fancy printing anything large. And anyway, I've got Una to print the large stuff.
The iBox prints "upside down" in that the build plate (which is not shown in the picture) is dipped in and out of the resin, with a new layer being deposited underneath the previous one. Each layer needs around 20 seconds to harden, but the great thing is that every layer takes the same time to print, which is better than the Ultimaker, where larger things take the print head ages to fill in.
The device is well put together. It uses a Raspberry Pi to control it and tiny stepper motor to drive the printing plate up and down. The Pi has a WiFi interface and you control the printer via an in-built web server where you can upload objects for printing and start print jobs.
I've not got around to firing it up just yet, but I'm looking forward to having a go.