How can I program the function keys on my MacBook?

I'd like to assign basic tasks to the function keys (or other keys if it's easier) on my MacBook. For example I'd like the following to happen when F1 (or whatever key) is pressed:

1. Launch Safari
2. Open a new window
3. Navigate to some specified site

Another example could be:

1. Launch Xcode
2. Open some specific project

I've experimented with the Automator for things like re-naming dozens of files in a particular directory but I don't know where to start for the above examples.

It's quite easy in OS X 10.6 Snow Leopard, by creating a new service. This is not supported in earlier versions of OS X. For example:

• Start Applications » Automator.
• Select "Service" for the template of the new Automator workflow.
• In the top of the right pane, select "Service receives no input in any application".
• Drag action "Run AppleScript" from the left pane into the workflow on the right pane.

• Replace the default with:

  on run {input, parameters}
  tell application "Safari"
  activate
  open location "http://superuser.com/"
  end tell
  return input
  end run

  

• Optional: click the Run button to test.

• Hit Cmd-S to save. The name you type will be the name in the Services menu. The workflow will be saved in ~/Library/Services.

Or, to have the default application open the file or location^†:

• Instead of dragging action "Run AppleScript" into the workflow, use "Run Shell Script".
• Leave Shell at its default "/bin/bash", and replace the default command cat with:

  open "http://superuser.com"

  or

  open "/Developer/Examples/OpenGL/Cocoa/CocoaGL/CocoaGL.xcodeproj"

To assign a keyboard shortcut, in 10.6:

• Open System Preferences » Keyboard » pane Keyboard Shortcuts.
• Select "Services" in the left pane.
• Scroll down to General in the right pane.
• Double-click to the right of the Automator workflow you just created.
• Press the keys you want to use (and if applicable, remove existing associations if you get a warning "Shortcut used by another action"), and switch panes to ensure the new shortcut is saved.

Unfortunately, it seems that this way Services cannot be assigned a function key (the key is displayed but remains in "edit mode", and when clicking elsewhere, it's lost, which is different from assigning function keys to built-in things like Exposé, or when adding an application shortcut).

To assign a function key, there are two options:

1. Assume that most applications have a Services menu, and hence will find the name like it appears there. So, if the service is named "Open Super User" then map the menu item Services » Open Super User:

   • Open System Preferences » Keyboard » pane Keyboard Shortcuts.
   • Select "Application Shortcuts" in the left pane.
   • Select "All Applications" in the right pane.
   • Add an entry for the exact name "Open Super User" and assign some function key.

2. Or, use the command line:

   • Find its hexadecimal keycode: F1 = \UF704, F2 = \UF705, ..., F6 = \UF709, F7 = \UF70A, etc.
   • Prefix that with any combination of @ for Command, ^ for Ctrl, ~ for Option, and $ for Shift.

   • Open Terminal. If the name of the service is Open Super User, then to map that service to F1, run:

     defaults write pbs NSServicesStatus -dict-add \
       '"(null) - Open Super User - runWorkflowAsService"' \
       '{ "key_equivalent" = "\UF704"; }'
     

     Or for Command-Shift-F12:

       '{ "key_equivalent" = "@$\UF70F"; }'
     

   • To make all running applications aware of the change you made using Terminal:

     • Close System Preferences if that was already running.
     • Find your new service in System Preferences » Keyboard » pane Keyboard Shortcuts like described above.
     • Disable and re-enable its checkbox to make every application aware of the change.

^{† There must be some AppleScript version of this as well, but I'm no expert... Anyone?}

You can use FastScripts to assign keyboard shortcuts to AppleScripts or Automator actions.

I don't believe there is a way to do so in Mac OS X without resorting to third party applications.

Quicksilver is one of these third party applications, and there is an excellent tutorial on settings up triggers in Quicksilver. With Quicksilver you can then set it up to activate whatever program you want to activate, and or even run external scripts that then do things such as Automator scripts.