All you need for this project is a 3/16 drill bit, super glue and a palm brush. Palm brushes can be found next to the dish washing liquid at your local grocery store. You may also need pliers if the palm brush has a post and spring in the center.
Before you can make your power scrubber, you need to remove the spring and plastic post that's inside some palm brushes. Simply take off the lid and pry the plastic post and spring out by pulling straight up. If you pull sideways you may crack the outter portion of the scrubber.
Put the lid back on the scrubber. Put your 3/16 drill bit into your drill and drill a hole through the lid and through the bristle area. Make sure to keep your bit straight while making the holes or else the scrubber will wobble when you use it.
Position the drill bit so that it is barely (less than 1/16 of an inch) poking through the bristle area. Without removing the drill bit from the scrubber, remove it from the drill. Carefully remove the lid with the drill bit still lodged inside the hole. Glue the bit to the top and bottom of the hole with super glue.
Flip the scrubber over on its side. Cover the hole and drill bit in the scrubbing area with super glue. Let the glue dry and you're ready to scrub like a beast -- just pop the bit back into your drill and get to work.