I don't know if this is available for windows users, but for MAc, on download.com, there's this program called Alarm Clock Pro that you can set your computer as an alarm. It can play a regular ring, any audio or video file, any itunes playlist or song, it can pause/play itunes play a random song. all this cool stuff. it will also open any web broadcasts or web pages at the time desired and send any email from a program like entourage at any given time (i guess for daily updates and such?)
i find it extremely useful. my alarm clock is now "glory glory to old georgia" at 3/4 volume from 400 watt speakers under my loft. definitely gets the job done.
its free with the option to buy full. I'm sure there are other cool programs like this out there, but i found this one to be the most user friendly.