Warbirds 4.00 was available to download from the developer's website when we last checked. We cannot confirm if there is a free download of this software available. This program is a product of NexusMedia. According to the results of the Google Safe Browsing check, the developer's site is safe. Despite this, we recommend checking the downloaded files with any free antivirus software. The program belongs to Desktop Tools.
From the developer:
With the Warbird Screensaver watch as 15 different warbird aircraft randomly fly across your screen. Set which planes you would like to see, as well as the sound of the props. Select a custom background to use from your favorite bmp files. You can include your company logo and a message as well. If you are an airplane lover then the Warbirds Screensaver is for you
You may want to check out more software, such as WW2 Warbirds Screen Saver or Aces High Pilot Stats, which might be related to Warbirds.