You've got about 15 minutes to wait in the doctor's office, but not 30. Fill that specific space with Longreads, an aggregator of great long-form writing that offers keyword search and a time/word count filter for your time-pressed reading.
Ideally, you'd be following Longreads on Twitter or their RSS feed, but if you're just looking for something good to read in 15, 30, 45, or hour-plus increments (and, hey, good for you on that last one), Longreads is chock full of good stuff. Pulling from magazines, newspapers, essay-minded blogs and other spaces around the web, you'll get good links when you search and often already in print-friendly form. It's a free service.