At some point as a kid, I put away childish things and bought a briefcase. Wait, scratch that. Actually, that should read: I bought childish things and put them away in a briefcase.
When I was growing up in the 2000s, we were living through the golden age of third-party gaming peripherals. I had an opaque plastic case for my Game Boy Advance that was designed to give the almond-shaped handheld the form factor of an off-brand GameCube controller. Similarly, the Wii got a blitz of plastic peripherals for the Wiimote to slot into so that, while you were playing Excite Truck or Mario Kart Wii, it would feel like you were holding a real steering wheel.
I also had several in the shapes of various kinds of sporting equipment so that when you were playing Wii Sports, you could swing a little plastic golf club or tennis racket. Before the Gameboy Advance SP introduced a backlight to the system, I had a light peripheral that attached to the top of my handheld so I could keep playing Pokemon, even as the sun set on my parents' minivan. I had several plastic cases that were shaped like a big DS cartridge, which could hold a dozen actual DS cartridges. I was living large.
The strangest, though, was a briefcase that was marketed exclusively to people who owned a Gameboy Advance. You can see an eBay listing for the model I had here. Created by Intec, this third-party accessory had a shining silver aluminum exterior, with horizontal metal ridges, and was padded on the inside with soft black fabric. It was sealed with metal clasps and you could carry it around with a black plastic handle. I don't remember why I decided to get it, but I do remember getting Pokemon Sapphire at the same time. So, it was probably my birthday, I was flush with gift cash, and decided to spend it on an unnecessary briefcase. What made that briefcase good for carrying around a Gameboy Advance specifically? Well, nothing really.
Except that, in the same way that LED lights and jagged race car stripes have come to signify "Gaming" now, in the 2000s, a metallic look communicated the same thing. My original DS was a sleek chrome, and the original iPods had reflective metal on the back. That was just what cool tech looked like for a few years. And, throwing that metallic look on a briefcase showed you meant business.
It was useful for carrying my Gameboy Advance, and later, my DS around. There were segmented compartments, like on a lunch tray, so you could store your console in one area, and your games in another, and your charger or spare batteries in a third. It's funny, in retrospect, that this peripheral was made for a handheld console specifically designed to be small enough to fit into your pocket. The gamer briefcase made the Gameboy Advance significantly less portable. But, that's the price you pay to look this cool. *slips on pair of Squirtle Squad sunglasses and games off into the sunset*