Helpful tip - Blackberry Curve
Do you have a Blackberry Curve? Are you having trackball issues? I've had my Blackberry Curve for quite a few months now, and I started having issues with the trackball being able to track left. Then, I started having issues with the trackball being able to track down. I realized I'd have to remove the trackball and clean it. Thankfully, the designers of the Blackberry Curve had made that quite simple:
1. Remove the ring surrounding the trackball. You can do this with your fingernail, if you wish. Be careful, the ring has tiny snap-in clips on the bottom, and you don't want to break these off!
2. Gently remove the trackball. No special tools are required, often you can simply turn the Blackberry Curve upside down after the ring is removed, and the trackball and housing will fall right out.
3. Use canned air to blow out the debris that has accumulated under the trackball inside the Blackberry Curve. Be careful not to blast the components too forcefully, or expel so much canned air that you cause a freeze up.
4. Carefully replace the trackball housing and outer ring.
Cleaning the trackball solved my tracking issues. I hope it does the same for you!