It's fairly standard to see people playing games at GDC – it's a gaming conference. But even so, in a hall full of similar-looking haptic controllers, a crowd quickly formed around one guy blasting stuff to smithereens on the PC version of Call of Duty: Advance Warfare with a rather realistic looking light gun and a disarming level of convincing gunfire noise.
In what Korean firm Uzbrainnet is claiming is "the world's first FPS gun controller", the Rail-Gun is an intriguing concept that uses the company's motion-sensing tech developed for its Motion Ring to replace mouse and keyboard with something a bit more punchy.
And while physical feedback is strong, accuracy impressive and response super-speedy, what's most intriguing is that as well as coming fully formed as a light gun peripheral for gamers, it's also aimed at the "gun enthusiast".
So if you just can't get down with orange-tipped faux-killing machines, no matter how realistic, and already have a haul of far more badass model guns at home, you can pimp them instead, as the system is built around four separate modules that can snap on to any firearm with accessory rails.
Frightening levels of accuracy are yours for the taking. And, hey, it's not missed a leap on to the increasingly over-crowded virtual reality bandwagon, either, as this rather ominous, military training-tinged Half-Life 2 Oculus demo shows: