+1 to the crockpot
Maybe not for most people, but for me, my stick blender. I make a lot of mayo, hollandaise, salad dressing, etc
Oil pan. Change your own dang oil ;) We live in a high rise and still change our own oil. Although we do get funny looks for it. (Totally allowed though, we checked our rental agreement).
Drying rack for clothing. Ironically, I don't own this yet. I've been hanging things on chairs and stools for a few years now, and keep telling myself I'll get a drying rack. They're like $20. I should just.... do that. And then be able to sit down for dinner, even on laundry day.
Trail pass. I have an annual trail permit, so I never have to worry about having cash on hand for trail fees. Means it's more convenient to do "free" (except for gas) outdoor activities, and ends up cheaper overall with how often we go.
Coffee grinder. I can buy larger quantities of coffee at once, and grind them fresh. It lets me buy more in bulk, ie cheaper per unit, and still have it be fresh. I buy from a coffee roaster that usually sells to businesses, but sells to public too if you come in and pick it up.