Last year, a group of crazily dedicated fans modded the iconic Tecmo Super Bowlto update it with current and correct NFL listings. One year on, they've done it again with (the unofficial) Tecmo Super Bowl 2013, featuring NFL teams and players fully up-to-date as of September 2. It's like one of those roster updates for Madden NFL 13, except for a 21-year-old NES classic.
It's surely an insane and time-draining undertaking to update Tecmo Super Bowl like this, let alone do it for two years running. If that inspires you to join in with the retro-current football fun, all you need is an emulator and the ROM file, and both can be found at TecmoBowl.org. Oh, and not a single measly dime because it's free.