Aurora is a great piece of free software (donationware), by Jonas Witt, that can turn your Mac (and iTunes) into an alarm clock.
It pretty much works as you would expect an alarm clock to work. You can schedule any number of alarms, set repeat days and times, etc… There’s even a snooze function that you can use with your Apple remote (if you have one). Aurora is even powerful enough to wake your Mac from sleep, or turn it on (if it’s off).
One handy feature that sets Aurora apart from a standard alarm clock, is its “Fall Asleep” function. You can start iTunes playing, and after a specified amount of time (or number of songs) Aurora will automatically fade the volume down, and either put your Mac to sleep, or shut it down all-together. That’s pretty cool.
So far, the only bug I’ve encountered, is in the time input field. The numbers you type aren’t what gets entered into the field. But, it’s not that important because you can easily set the time with either the arrow keys, or the arrow buttons next to the input field.
Aurora is free, but if you like it, you should consider making a donation to the developer. It’s well worth it.
found via TUAW