Even though it can be controlled by an iPhone, Desk Pets's $30 ( Macworld rated 4 out of 5 mice ) has a bit of a mind of its own. It has two activity options that cause it to wander around by itself--either in Amazing Touchless Navigation mode, which uses an infrared sensor to avoid obstacles, or in Autonomous Personality mode, which uses various pre-programmed patterns for moving and displaying light and sounds. The Tankbot's tank-inspired treads allow it to navigate the most treacherous obstacles on your desk, yet it's light enough to run over your keyboard without pressing any keys.
In either activity mode, the Tankbot wanders around, making what can only be described as velocirapter-like noises as it approaches objects. The only navigational problem is that in Touchless Navigation mode, the vehicle didn't always stop when it approached black objects. For example, when it approached a pile of black wire on the floor, it continued forward it until it eventually flipped over onto its back. The Tankbot also has some trouble with the edges of furniture, since its sensors are looking for objects completely blocking its path. Luckily the Tankbot can handle a little bit of a fall, though the first time this happened, while the vehicle was lying on the floor upside-down, I experienced a feature that made me simultaneously love hate the Tankbot more: It cried.
When you want to take control of your Tankbot--called Smartphone Control mode--you plug an infrared transmitter into your iOS device's headphone jack. You then use the free to drive the Tankbot from up to three meters away using two onscreen joysticks and a Stop button. (The transmitter uses L1154F batteries--a fact that I discovered when the included batteries died.) The two-joystick interface is not as intuitive as iOS-controlled vehicles that use your iOS device's built-in accelerometer, or even a simple 4-direction controller, but after using it for a few minutes, I found it was easy enough to get the hang of it. The Tankbot is very responsive, as well.
The Tankbot charges using a flip-out USB connector. When plugged into a USB port on my MacBook Pro, the Tankbot stuck conveniently out of the side. When charged, the Tankbot can run around for about 15 minutes before slowing down.