A few years ago I picked up a SwiftPoint 300 mouse which is a great little mouse that you can use as an alternative to your trackpad. Today I found it again in a draw and decided to try it out again. The only issue is that all my movements were inverted, i.e. moving the mouse up and down made it go left and right instead! The solution is actually to use the mouse's built-in calibration feature, as described on their official site:
1. Hold the mouse at a comfortable angle.2. Press and hold down both mouse buttons.3. After 2 seconds the mouse pointer will position itself at the bottom of the screen and move upwards.4. Release the buttons and move the mouse pointer in a straight line upward until the pointer moves in a small circle. The new up direction will now be set.
At point 3, as it moves up, continue to slide your mouse up in the same direction - this wasn't made clear in the instructions. It now works fine again. I've made the note here in case the official site goes offline.