There are a few schools in the district that record "podcasts" of the morning announcements for teachers to play from their computers rather than broadcasting them over the intercom or printing paper copies for teachers to read.
It's not as difficult as it sounds. Basically all you need is a microphone, perhaps one from Rock Band for about $20, and free software on your computer, such as Audacity. Click the record button, read the announcements, save it as an mp3, and post it on your webpage or "Staff News" folder.
If you want to get fancy, you can allow people to subscribe to your podcast (check out a previous post), or even record video like a morning newscast.
You just need a staff member or two, and perhaps some students, and you can have a daily (or weekly) announcements podcast.