As part of a larger project, I have been working to simulate an alert from AIR ala TweetDeck. Attached to this is the results of that work. I stripped the alert out so that I could share it. I have included the AIR application as well as all the source code.
The application example is very simplistic. It is just an AIR html window with a button to launch the alert. In the larger application this came from I launch the alert as a response to a BlaseDS message. The alert window is actually a styled, transparent AIR window.
Now, let me try and explain the workings of the code. The first part is the launching of the alert window. Using "air.Capabilities" I am able to get the resolution of the users screen. This allows me to create positioning so I can place the alert top right on the screen. Next I set the options for the window. These options just create a transparent window with no header/footer or other controls. The last part is just the click action to launch the window and have it load the html file into itself.