In what started as a simple robot and ended up as a great example of 'feature creep' is this fine example by Instructables user "nicoo". Using a robotic vacuum cleaner as a base (the "Roomba") they fitted an arm and with six servos created a device that can go about picking things up and collecting them. One Arduino controls the Roomba for motion, and another controls the servos. The user interface is a pair of Nintendo Wii controllers - and interestingly enough they've used the serial interface of the Roomba for direct Arduino control. Amazing.
If you found the project above interesting - but not sure how to start with Arduino - then the best way to learn is with our Experimenter's Kit for Arduino:
The package includes a wide variety of parts, sensors and modules including: a servo motor, lights, buttons, switches, sound, sensors, breadboard, wires and more. Furthermore a Freetronics Eleven Arduino-compatible board is included to make this an extensive hobby experimenter, inventor and starter kit. However we don't leave you alone to figure it all out, included is a great project and instruction booklet, plus access to a supporting web page and software examples. In other words - this is everything you need to get started for a fun range of electronics and Arduino related projects!
So to get started or for more information and to order, check out the product page.