Jez:Static dust cleaner. If cleaning disc (cd or dvd) always clean in a straight wipe (top to bottom/ right to left) from one side to the other. People have a tendencie to clean thier discs like records, giving a greater chance of damage to the disc.
I though the preferred method was radially - i.e. from centre outward. The basic plan is to try to ensure any marks are radial (and therefore normal to the data track, giving less chance of diverting the laser tracking system). Any other method could potenially leave marks that are tangential to the track and could cause mis-tracking.
Generally speaking, you aren't learning much if your lips are moving.