Introversion Software and Ambrosia Software have announced plans for a DEFCON freeplay long weekend in conjunction with the Penny Arcade Expo. The event is scheduled to begin on Friday, August 24 at 18:00 GMT and runs until Monday, August 27 at 06:00 GMT.

To take part head over to and download the free trial version of DEFCON. Once the clock strikes 18:00 on August 24 the demo restrictions will be lifted and gamers will have access to the full game.

If that's not soon enough the full game is available to purchase from Introversion's online store and from Steam. Mac users can find a Mac specific version over on the Ambrosia Software website.

For more on DEFCON head over to the DEFCON game space where you find a review and a host of screenshots.