Here are a couple of projects I messed around with this weekend.
First is an enclosure for the power supply, arduino, cut-off switch etc. Not populated yet, I actually have to cut another one because I accidentally made it about 1/8" to small for the power supply.

Made out of 5mm sanded birch plywood.
Next is just an interesting idea I had for a mini book shelf. Made out of 3/8" rough plywood, just a prototype for now. I'm gonna add one more level but that seems to be the stability limit for this design.
No glue or fasteners yet, I just made the slots about .01" undersize, seems to work pretty well.
Here it is on the test bed.