Lenovo offers its Lenovo M0520 Multimedia Stereo USB 2.0 Speakers in Black, model no. 57Y6360, for $29.99. Coupon code “USPC11AG26360” drops them to $10.50. With free shipping, that’s the lowest total price we could find by $21, although we saw it for a buck less two weeks ago (since expired). Sales tax is added where applicable. This USB-powered round speaker system features a 90Hz to 20kHz frequency response, 3.5mm audio jack, and more.