When I play Black Jack, I swap my small chips for larger ones as a control mechanism. I only allow myself to play with, i.e. spend, the small chips, and I walk away with whatever large ones I manage to accumulate. At work, I’ve adopted the same mechanism lately; I swap $20’s for hunneds as I make them, and every hunned I make becomes untouchable, for deposit only. Those annoying shifts where I don’t quite break the next $100 mark, or don’t break it by enough to have adequate spending money, I get a fiddy, which I’m equally unlikely to spend versus deposit.