Astro Gaming wants you to play Metal Gear Solid: Peace Walker the right way: with a headset larger than a PSP and almost as expensive. The company has unveiled a special Peace Walker version of its A30 headset, featuring Peace Walker imagery on the earphones. It has the same cross-platform compatibility as the traditional A30, and the same ability to swap out the graphics.
If you want the sides of your head to bear the Peace Walker logo (and if you also want to hear sounds and stuff), you can pick one of these up for $150. You can also add $20 and get a downloadable boxed copy of the game, which is probably something you want, considering that you're hypothetically going to drop crazy bucks on a headset with its name on it.
[Update: corrected the bonus offer: $20 gets you a retail, packaged copy of Peace Walker.]