Power glove is a piece of training equipment. Power glove is not a product though. It is a silly name for an equally silly idea. the idea is that playing with big glove that restricts finger and wrist movement improves mouse control and overall skill.
yes, i realize this "idea" is likely not original, but rather unpopular due to its silly obsessiveness. despite this, i believe the power glove (ie wearing a huge glove on the mouse hand) can help players improve.
mouse control can be divided into two categories. Arm movements where the curser covers large distances, and hand/finger movements which make up for the inaccuracy of the arm moevement. The arm movements are performed by sliding the mouse straightly and flatly across or up and down the surface. The small ones are done by the wrist pivoting on the palm as well the fingers bending by pivotting at the tips of the fingers that rest on the mouse.
wearing the power glove inhibits small movements and improves big movements. the fingers of the glove restrict the claw-like movements, and the wrist of the glove inhibits the hand-wave motions. this reduces the speed that you are able to select things on the map. the result of this reduced speed of precision mouse movements is a need to compensate with the arm. powerglove makes compensating with the arm easier because the fabric of the glove makes less friction. Voila! you have a method of isolating your arm movements, allowing you to improve your mouse control.
photo of the powerglove http://www.imagebam.com/image/0ba9b3171765172