In any case, my time in the wood shop has been less often, for shorter durations, and with more interruptions lately. I tried to find tiny projects I could complete in 90 minutes or so after he and my wife went to bed.
This is a little puzzle I found on Roy Underhill's The Woodwright's School website. Casse-Tete Diabolique, which is French for Diabolical Puzzle.
I made it out of scrap hem-fir as an initial practice attempt, using only hand tools. This was wise because I learned the importance of hard wood and tight-fitting joints for this particular puzzle. The more it gets used, the more the wood gets pushed around, the looser it becomes, and the easier it is to solve. Though I find it interesting that while it's incredibly easy for people to take apart, they never remember what it looked like initially to put it back together. :P