With "Switch-It", you can use the keyboard to switch between applications:
•  Hold down the activator key (Command) and press the switch key (Tab) to cycle through the running applications.
•  Release the activator key to actually switch to the application.
•  The switch request can be canceled by pressing the cancel key (Escape) before releasing the activator key.

While cycling through the running applications, you can also:
•  Access directly to the Finder ('F').
•  Request the termination of applications, by selecting them either individually (quit: 'Q' or 'X'), or globally (kill-all: 'K').