DAR.fm is simply put a way to record digital radio on the Internet and play it whenever you want. This service is currently in Beta, so it may play up from time to time. Having said that, it may well be a very useful service.
Here is a great site for sermons. You are able to download both MP3s and videos of the sermons. For a number of sermons there are PDF transcripts available – if there aren’t any available you can pay a fee to have one done for you.
It is a great site, with not only sermons available, but other forms of teaching available also. The latest in Christian news can also be found via this site.