Spinnies, available at Warby Parker, from $95
Thanks to a special design, these sunglasses can rotate 360 degrees smoothly. Sure, they're a little gimmicky, but they're also fun and proceeds go to a good cause. 100% of your purchase goes toward a program called Pupils Project, which provides free vision screenings, eye exams, and glasses to school kids in the US.
The versatile black matte sunglasses have UV ray-blocking, scratch-resistant lenses, and are available in a wide width design.