Groupon offers the Liger Blaze Sweatproof Bluetooth Headphones for $39.99. Coupon code "SALE3" cuts it to $35.99. With free shipping, that's tied with last week's mention as the lowest total price we've seen. (It's a current best by $9.) Features include built-in control buttons and mic, passive noise isolation, two sizes of earbuds, up to five hours of playback, and Bluetooth 4.1. Deal ends April 22.