In nature, the only way for animals to achieve perfect vision is to crossbreed with an eagle, usually resulting in eagle-eyed abominations such as snakes with talons and flying pumas. Keeping human senses sharp is a less formidable task, as today’s Groupon proves: for $40, you get $160 toward glasses or prescription sunglasses at Eyecare Greengate in Greensburg.

Eyecare Greengate corrects on-the-fritz ocular orbs with a plethora of image-sharpening lenses and stylish frames by brands such as Prada, Ray-Ban, and Lafont. Guests browse the selection of more than 1,000 frames ($89–$1,150), picking out specs that mesh with personal style or facilitate the infiltration of subversive librarian cells. Lenses ($70+ for single-vision plastic lenses) encompass basic options as well as such high-tech innovations as progressive, lightweight, and photochromatic lenses. Allow for up to 30 minutes to try on and order a smart pair of specs. New frame-lens combos allow the freshly clear-sighted to jet back home and determine whether the flamingos in the neighbor's yard are real.