I have a script that uses random lyrics to change your PSM. You can set how often it changes, and how many lyrics you want to be used before a single lyric can be repeated. Would be very easy for you to change the source code to add/change to quotes if thats what you would like, you can find it attached to my post in this thread
http://shoutbox.menthix.net/showthread.php?tid=75840&pid=833625#pid833625