There are just so many things that can be done with the iPhone/iPod Touch, and now you can use it as a wireless touchpad mouse to remote control your system.
Touchpad Pro is a freeware application that turns your iPhone/iPod Touch into a multi-touch wireless mouse for any operating system.
As the same as all other free applications, you will need to jailbreak your iPhone/iPod Touch and install Touchpad Pro from the installer.app.
On the operating system side, you will need to install VNC to enable remote connection (VNC is already pre-installed in Mac Leopard).
Configuration can be easily done by entering the IP address and password of the system you are connecting to. Once its is up and running, you can use your iPhone/iPod Touch like a MacBook Air trackpad with touch movement like two-finger scroll and double-finger-tap right-click
The free version of Touchpad Pro only allows you to use your iPhone/iPod Touch as a touchpad mouse, the latest version includes a screenview function where you can view the screen of the remote system. The screenview function requires an activation fee of $15 Euro.