This Bluedio BS-2 Explorer Mini Wireless Bluetooth Speaker Sound System in Black or Silver drops from $79.99 to $19.99 at Newegg Marketplace. It will ship for free from Bluedio's official flagship store. This is the lowest price we could find for one of these well-reviewed speakers by $10. They have a seven-hour battery-life, Bluetooth 4.1 with a 30ft range, built-in microphones, and toggle-able audio effects. There is no sales tax (except in CA, NJ, TN).