T-Mobile offers its T-Mobile Rocket 4G Laptop Stick with a $15 T-Mobile Refill Card for $19.99 with free shipping. (Refill card is added in-cart.) That's tied with our mention from a month ago and the lowest total price we could find for the Rocket 4G alone by $40. Sales tax is added where applicable. This USB modem features HSPA+ speeds up to 21Mbps, microSD card slot, and more.