Newegg offers the Seagate Backup 4TB USB 3.0 External Hard Drive, model no. STDT4000100, for $139.99. Coupon code "EMCAXKS74" drops the price to $114.99. With free shipping, that's $2 under our mention from last fall and the lowest total price we've ever seen. (It's also a current low by $5.) It features mobile backup via an app for both iOS and Android devices. Deal ends September 21.