Lion has brought with it a boatload of new features including Mission Control and Launchpad. Apple is releasing new keyboards that allow you to activate these new features with F3 and F4 respectively.
If you are using an older keyboard, your F4 key is stuck launching Dashboard instead of Launchpad. That is, unless you download FunctionFlip and Quicksilver to remap the keys.
The process involves downloading FunctionFlip to reset your F keys to work as standard Function keys rather than launchers. You are then able to use Quicksilver to remap the keys to do whatever you want.
We suggest leaving everything the same with the exception of the F4 key. You can remap this key to run Launchpad.app, which you will find in your Applications folder.
Since the new default behavior is for F4 to activate Launchpad, changing only this key will allow anyone familiar with Mac to still sit down and work seamlessly. If, however, you want to be selfish and don’t care about other people’s feelings, feel free to hack F1 – F12 to your heart’s content.