Best Buy has the Orbotix Ollie By Sphero App-Controlled Robot (blue) for $50 with free in-store pickup only*. Sphero BB-8's barrel-shaped cousin that rolls up ramps, drifts, spins, twirls, and does other things that the droid can't. Top speed of 14 MPH. Programmable and controllable via Android or iPhone.
*Click the blue "check stores" button to find your local store, then click "Add to cart."