Open windows are much cheaper than air conditioning, but many houses provide unwanted physics lessons when drafts start slamming doors around. This relatively cheap, good-looking doorstop keeps your open doors in place, no matter the weather.
Don Allen at the excellent Cool Tools blog notes that Stanley's brass finished doorstops aren't exactly silent when they make their connection, and that you'll likely need to get out the measuring tape and be precise in putting them in. But both the cost and effort seem a small price to pay — especially if you're regularly scared out of your mind by the sudden sound of a door slamming when nobody else is home. With summer approaching, it's also a smart way to make sure your air conditioning is circulating where you want it.
Stanley's magnetic doorstop goes for just under $US9 on Amazon, though there are certainly other finishes and variants you can pick up.