Between Sony, Nintendo, Sega and Atari(!), the console wars of the early '90s were mighty fierce. E3 in 1995, though, was the beginning of the end for Sega, and it was all because of one number.
At the time, both the Sega Saturn and the Sony PlayStation had been released in Japan but were awaiting a US launch. Sega at its press conference hoped to score an advantage, announcing that the Saturn would be available immediately for $399.
In a game of one-upmanship, Sony's Steve Race took the stage at PlayStation's press conference for a three-word speech: "Two ninety nine." The crowd was much more responsive to that price.
In the end, Sega's hot-shotting the Saturn worked against it. The system launched with a limited supply, with few games and too high a price.
When Microsoft announced the Xbox One prior to E3 2013, a big kerfuffle was made about its always-internet-connected features. Most controversially, there would be a restriction on used games, including discs you borrow from friends.
Sony had fun with this, playing a video at E3 that year demonstrating how to share games with friends. It's fairly savage. Watch it here.
The franchise had been synonymous with PlayStation since 1997, when Final Fantasy VII was released for the PS1. That's why it was such a shock to see Lightning, the heroin of Final Fantasy XIII, show up on screen at Microsoft's 2008 E3 press conference.
It was a huge blow for Sony, which for the PlayStation and PlayStation 2 years enjoyed a monopoly on several key franchises.
Speaking of highly anticipated, by the time of Bethesda's (first ever) E3 press conference in 2015, it had been five years since the release of Fallout: New Vegas. When it came time for Fallout director Todd Howard to demo the game, the crowd was absolutely in the palm of his hand.
In 2007, Valve co-founder Gabe Newell famously called the PlayStation 3 a "waste of time." So you can understand everyone's shock when he was invited onstage at Sony's press conference in 2008.
"I've been pretty outspoken in my comments about the current generation of game consoles," he opened, much to the crowd's amusement. He would go on to not only announce that Portal 2, the sequel to the universally beloved Portal, would be coming to the PlayStation 3, but that the PS3 would be the best place to play it.
The Portal 2 announcement wasn't Newell's first E3 moment of glory. In 2003, he gave an extended demo of Half-Life 2, a much-anticipated followup to 1998's Half-Life.
It may look standard now, but the ability to interact with the environment -- by blowing enemies to their death via a spinning fan, for instance, or using the explosion of a flame canister to hurl a car at them -- was revolutionary at the time.
To this day, fans dream of the E3 when Half-Life 3 is demoed. One day, everyone. One day.