3D printer in Minecraft
Derryl Murphy sez, "My son is home sick and found this video showing a 3D printer ItsJustJumby created for working inside the world of Minecraft. The engineering is way beyond the two of us, but we both still find it amazing and fascinating."
I could watch this all day. The description's actually very clear, and extremely clever. Great engineering smarts on display.
3D Printer With 16 Colors - Minecraft Invention (Thanks, Derryl!)