Takeya Cold Brew Maker | $16 | Amazon | Clip coupon on page
Iced coffee is a brilliant way to sell people ice for the price of coffee (which is mostly water to begin with). Cold brew on the other hand is a different process that results in less acidity, among other benefits, and you can do it yourself at home with this top-selling Takeya, now down to $16 on Amazon after you clip coupon on page, within about a dollar of an all-time low.
This non-coffee drinker bought one of these a couple years ago, and I loved the thing (though admittedly, I have since upgraded to the OXO alternative). All you have to do is fill the basket with ground coffee, fill the container with water, and let it steep overnight in the fridge. The resulting coffee concentrate needs to be watered down, so one batch should last you several days.