Mac OSX Lion comes with "natural scrolling" (reverse scrolling) and if you're using it on one of your computers, you probably got used to it. But switching between computers can get really confusing so maybe you want to use Apple's Natural Scrolling in Ubuntu too.
Here's where Natural Scrolling Ubuntu appindicator comes in: this application lets you easily enable/disable inversed Mac OS X Lion like "natural" scrolling under Ubuntu. To add the PPA and install Natural Scrolling indicator under Ubuntu Natty or Oneiric, use the commands below:
sudo add-apt-repository ppa:zedtux/naturalscrolling sudo apt-get update sudo apt-get install naturalscrolling
Then, launch Natural Scrolling and a new indicator should show up. Using it, you can easily enable/disable natural scrolling (useful if someone who is not used to natural scrolling uses your computer).
For now, the PPA provides an icon for Ubuntu Mono Dark (light panels) only.