JD Warren is a maker and tinkerer. He has been featured on the cover of MAKE magazine (issue 22) with his remote controlled Lawnbot400 and is the author of Arduino Robotics.
The Segbot is a balancing, rideable segway clone built from scratch for around $500. It uses an Arduino, gyroscope, accelerometer, Sabertooth motor-controller, and large power wheelchair motors.
The Lawnbot400 is a remotely controlled lawnmower that makes mowing the lawn less of a chore and more of a game. It can operate for 4-6 hours in between charges and can carry a human.
Other assorted robots include remote-controlled, line-following, wall-following, and bluetooth controlled.