If you have got it flaunt it! Flaunt It is a WordPress plugin to display scheduled announcements. Configure it to show announcements between specific start and end dates, on certain days of the week or during some time of the day. You can structure your announcements in categories, and then display them on pages or posts, or with a widget.
The announcements are custom type posts so you can style it as you wish the same way that you do with your regular posts.