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No, it can't. The term perpetual motion, taken literally, refers to movement that goes on forever. However, the term more generally refers to any closed system that produces more energy than it consumes. Such a device or system would be in violation of the law of conservation of energy, which states that energy can never be created or destroyed, and is therefore impossible. The most conventional type of perpetual motion machine is a mechanical system which (supposedly) sustains motion while inevitably losing energy to friction and air resistance. No such device to this date has been or ever could be created.

Essentially all perpetual machines lose energy in some form or other. The law of conservation of energy cannot be broken, you cannot creat energy. A nice example is seen in the film Alien 2, a shot of a metal bird dipping its beak into a glass of water after they have been in deep sleep for several months. While that bird could continue to dip its beak for many months to come it would eventually cease to do so. Someone gave it energy by setting off the motion but the friction of its motion in the limb that allows it to dip, the passage of its body through the air (friction again), the retraction of its beak from the water (friction) however small always draws energy away from what was given. This law cannot be broken and the third law states that, while it may be possible to create a device that will roll or fall or spin forever, as soon as you try to extract energy from it you break the 2nd law and the device will stop working.

See:

http://en.wikipedia.org/wiki/Laws_of_thermodynamics

http://en.wikipedia.org/wiki/Perpetual_motion

http://www.lhup.edu/~dsimanek/museum/unwork.htm

http://www.kilty.com/pmotion.htm