As one of its daily deals, Best Buy offers the Insignia 2.1-Channel Bluetooth Speaker System in Black, model no. NS-PSB4521, for $19.99. Opt for in-store pickup to avoid the $9.49 shipping fee. That's $10 under our February mention, $30 off list, and the best price we could find. It includes a subwoofer and two speakers and allows pairing with up to eight devices. Deal ends today.