You could reassign the keys needed for Exposé and Spaces, no? I have a early 2008 MacBook so all F-keys except F5 and F6 are occupied by various system control buttons (play/pause, dashboard etc).
Volume control is a simple premise on Android phones. You hit your volume rocker, set your volume, and go. You can also set your notification, call, and media volumes independently. However, that is ...