Yugster offers the Monster Digital OverDrive Advanced External USB 3.0 128GB SSD, model no. SSDOM-0128-D, for $39.97. Coupon code "FreeYugBuck" drops it to $38.97. With $5 for shipping, that's the lowest total price we could find by $26. It features 140MB/s read and write speeds.
Note: The countdown timer on the Yugster product page does not reflect an actual expiration time and resets daily.