But perhaps we underestimated laundry detergent when we never considered using it for anything other than to launder. If only we had been a little more open-minded, and hadn't spent so much time standing in the aisle at the grocery store trying to work out the math of how much money we'd actually save in the long run by buying the economy size instead of just grabbing the cheapest one, we might have been able to see what one eagle-eyed Redditor beat us to.