Star Citizen's dogfighting module is free for everyone to try out until August 19.
The company developing the game, Roberts Space Industries, offered the download for free to anyone attending Gamescom 2015. Apparently, it's possible for absolutely anyone to sign up for it, because the code they provided to GC attendees has unlimited uses.
Keep in mind that the download weighs in at 26gb, so you better have a high-speed internet connection or you're going to have long to wait before you can play it.
So here's what you can do to play the game.
1) Go to this address.
2) Choose Enlist Now to create a new account.
3) Once the account is created, enter GAMESCOM2015 into the coupon field and hit Apply Coupon.
Enjoy!