X/Y Plotter in a Box
Here is one I did just for fun. Yup, its a whole X/Y plotter and yup, its in a box! Woo Hoo!
Its a pretty simple setup, the Y axis is via a 2" aluminum drum, the X axis slides on rails much like any 3d printer or the like, and the Z (pen lift) is a simple spool that winds up some fishing line to draw the pen back. A simple return spring keeps the pen against the paper. --Its a fancy-schmancy actual plotter pen, by the way.
Construction is a bit of everthing, little CNC, some laser cutting and some manual work on the lathe. All in all, I might have 20 hours into it. All parts were stuff I had on hand.
The brains consist of an Arduino Nano running GRBL and a very simple desktop app is used as a G-code feeder. All "drawing files" are produced via CamBam --The same software I use to produce cut files for my CNC and laser cutter.
It turned out pretty good, I think, but I have no idea what I am going to use it for. :)