Twitter user Wanikun left his Super Famicom (the Japanese name for the Super Nintendo) on for over two decades to preserve his save data for Japanese game Umihara Kawase.
As reported by Rocket News 24 (via Nerdist), the game came out in 1994, and some game cartridges back then had a static RAM partnered with lithium ion batteries. If the batteries stayed charged, your game would stay saved. Wanikun's battery started to fail, and since then he's kept the console plugged in and turned on -- with one exception. He was forced to unplug it for a short amount of time while he moved to a new house. Thankfully, the battery stayed alive.
This dedicated gamer estimates that he's had his console turned on for over 20 years and in operation for over 180,000 hours. If he turns it off, he says, he'll probably lose the precious data he's been keeping alive all these years.
Thankfully, preserving your saves isn't as hard as it used to be. We don't have a guide on transferring your saves from your SNES to your Wii U, but we do have one from the original Wii.