Just a quick update to the script...
iTunes 2 is much more scriptable; although they will still work, you don't need to do the event hookNext and event hookPlay commands. You can just use "play" and "next"
I don't believe cron will wake up a sleeping computer. And from what I can tell about Tempus (the utility mentioned above to perform cron jobs while sleeping) it won't actually wake up a computer to run the job. The first time the computer wakes, tempus will check to see if any cron jobs were supposed to have been run with the computer was sleeping.
So, if you used Tempus to run all this stuff, it would start playing music after you manually woke the machien up. You'd probably have missed your classes or work by then, though. Safest bet is still just to leave your computer running and not sleeping. (You should use all those extra cycles at night for something useful, like ,
encryption research,
curing diseases or
finding life on other planets.)