The Mighty Mouse is a great product, but never a perfect one. After a while using it, the scroll ball can gather enough dust to make it completely disfunctional. I've seen a few descriptions on how to clean the scroll ball with a cloth and some cleaning products, and a few descriptions on how to open the mouse, but still I decided to make a detailed instructable on it.

Step 1: What You'll Need

- An Apple Mighty Mouse =D
- An Olfa cutter (or any craft knife you're used to)
- Super glue
- A precision philips screwdriver

Step 2: Remove the Outer Ring

This is optional. I've seen some people opening the mouse without removing this outer ring, but then the cord will prevent you from separating the two halves and it will be a bit hard to work. So I prefer taking more time on this to make the process easier later.

- With the craft knife, start to unglue the ring from the side buttons. It's glued to the body at different points, so every once in a while you'll hear a snap of the glue coming loose.
- Carefully work your way around the base until the whole thing is free. It will seem very hard around the bottom part especially, but eventually it will come loose.

Be extra careful and take your time. The ring is fragile and flexible, so try not to bend it while doing this, or you'll end up with something like this.

Step 3: Crack It Open

- Use the precision screwdriver or the knife to snap loose the base from the body. A little leverage with the tool should do the trick.

This is where that retaining ring would be holding the cord to the body, but as we've already removed it, the parts are independent, except for the inner cables.

- Carefully unplug the two inner cables by pushing out the black jumper that holds them in.

Step 4: Release the Ball

This is where things start to get really fiddly, so be sure to do it on a straight surface to prevent any pieces from rolling off.

- Unscrew the black cover that holds the scroll ball.
- Unsnap the inner piece from the black cover, by pushing in the locks on the side.
- Take out the center piece from the metal case and unsnap it apart.

Step 5: Clean =D

- Carefully clean out each of the four rollers and place them back, so you don't lose the orientation.
- Clean the ball if you need to and place it back.
- Now just put everything back together until you're left with the mouse and that unglued retaining ring.

Step 6: Glue Back the Ring

This is also optional. If you want to keep the ring off, to ease the next cleanup, it'll work fine. However the cord is held in place by the ring, so without it the cord will sometimes get in the way of your mouse.

So what you need is only a couple of drops of super glue to keep the ring fixed. One on each diagonal edge of the base.

A few moments to dry and your Mighty Mouse is mighty again!