Currently Being ModeratedFeb 16, 2013 6:44 AM (in response to osihara)
Create an Automator Service that receives no input.
Add an Applescript action and modify it for your Applescript.
Save it and assign a shortcut in the Keyboard System Preferences.
Currently Being ModeratedFeb 16, 2013 10:09 AM (in response to osihara)
You could put the applescript into a workflow in automator and save it as a service. Then you could assign the function key to it with a keyboard shortcut in system preferences > keyboard > keyboard shortcuts. I use Quickeys for this sort of thing.