Lenovo offers its Lenovo BT820-US Bluetooth Speaker, model no. 0B54211, for $79.99. Coupon code "USP1SP344211" cuts the price to $19.99. With free shipping, that's $2 under our May mention and the second-lowest total price we've seen. (It's a current price low by $33.) This 2-channel unit features two speakers and a 3.5mm jack; it can be powered by the included AC-DC adapter or four AA batteries (not included). Deal ends September 17.