Wow that article hit a bit close to home. I decently have had my spurts on side business with scrapping cars, or selling stuff on Craigslist.
Even though I get tons of hours of vacation overtime is way too tempting, 12 hour minimum shifts all at double time, working a 14-18 hour shift , getting a few hours rest and coming back the next day for overtime. It is a bit crazy and the body feels it, but 4 figures in 2 weeks feels amazing at the end!