In 2004, people started creating something called machinima. Machinima is when people use video games to make their own animated movies. It's like using toys to make a movie, but instead of toys, it's video games.
During this time, lots of people were making machinima using a game called Halo. They would use the game to create their own stories and characters, and then share them on the internet.
One of the big machinima movies that came out in 2004 was called "Red vs. Blue". It was created by a group of people called Rooster Teeth, and it was really popular. People loved watching the funny and silly stories that the characters got into.
Other machinima movies that came out in 2004 included "War of the Servers", which was a big battle between different videogame servers, and "Swordy Bunch", which was about a group of knights fighting monsters.
Overall, 2004 was a big year for machinima, and many people were excited to see what new stories and movies would come out using this new way of creating animated content.