Tibetan Buddhists believe that saying the mantra (prayer) Om Mani Padme Hum, invites the blessings of Chenrezig, the embodiment of compassion.
They also believe you can produce the same effect by spinning the written form of the mantra around in a prayer wheel (called “Mani wheels” by the Tibetans). The effect is said to be multiplied when more copies of the mantra are included, and spinning the Mani wheels faster increases the benefit as well.
His Holiness, the Dalai Lama, has said that having the mantra on your computer works the same as a traditional Mani wheel. As the digital image spins around on your hard drive, it sends the peaceful prayer of compassion to all directions and purifies the area. Animated images like this one are digital Mani wheels.