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?
I got a Winix A230. There’s a program in my state that offers discounted products if they’re energy effecient, save water etc., so I got it for $79. I was pretty skeptical about air purifiers in general, but this thing will ramp up if I fart from across the room, so it’s doing something. And it’s helped a ton with my allergies.