Without window tinting, cars would be forced to reveal all of their guilty pleasures, whether it be a penchant for Hello Kitty seat covers or the outdated practice of filling the glove box with actual gloves. Keep vehicular secrets safe with today's Groupon: for $145, you get window tinting for five windows at BumperDoc (a $290 value). Choose between locations in San Diego and Santee.

BumperDoc's I-Car Platinum-certified shop managers oversee an experienced team of specialists as they tint windows of autos of every make and model with Solar Gard film. After scheduling an appointment over the phone or with Morse code tapped on the garage’s plumbing, customers can roll their rides into either shop where technicians will carefully apply tints available with 5%, 15%, 20%, 30%, or 35% visibility. Designed to block out up to 61% of total solar energy and 99% of ultraviolet rays, the film works to keep interiors cool and safe from the sun's attempts to fade fabrics or replace airbags with whoopee cushions. To prove their ability to the entire Internet, BumperDoc's staff has filled an online gallery with photos of their window-tinting efforts.