Sometimes you need to put down the AK-47, pause the terrorist hunt, and play Super Mario Bros. Using a server plugin, a clever modder that goes by the name skwumpy created the Sourcemod Entertainment System or SMES, which lets players interact with a functioning Nintendo within a Counter-Strike: Global Offensive map (see above video for a demonstration).
To play, you press the action button (default: 'E') to pick up a cartridge, again to insert, again to power, and again to play. Skwumpy put a lot of detail into this, including animation, sound, physical wiring, and a playable Mario clone called Super Mareo. Why it uses a Super Nintendo controller, I'm not quite sure. Maybe it's really Super Mareo All-Stars.
"The system originally was just going to be direct input to the TV in cs_office, but I got a bit carried away! The system now features a video game console, game cartridges, controllers, and wires to connect them!!" skwumpy wrote on the video's description.
If you want to see it in person you can go to CS:GO server 22.214.171.124
Random Time! - A working NES within Counter Strike [GoNintendo]