When it comes to love letters to video games, I think it can be said that the Super Smash Bros. series is the biggest living video game love letter to date by a large margin. Sure, there are other big video game crossovers out there, but Sakurai's famous platform fighter pays tribute to so many titles, large and small, purely out of love for the medium and nothing else. The dedication spreads far and wide, yet remains in the realm of video games at all times.
