For me, it was a pair of merrell shoes on sale. They have lasted 3+ years, have great grip in the snow and ice, and so comfortable, my feet don’t hurt after wearing all day.
Never cheap out on anything that comes between you and the ground; shoes, tires, a bed.
What have been some of your good purchases under $100?
My noise cancelling headphones are the only reason I survived so far. At first I felt like I was being a bad parent, but I realized wearing them made me a better parent. Like you said, I was able to stay more rational and disconnect a little from the screaming.