There has also been a fully playable version of Quake that runs in the browser for many years. Super cool, was great for slacking off at work back in the day haha
Edit: Quake Live it was called. Unclear if it's still offered in the browser as it seems to have made it's way to Steam.
Edit: Quake Live it was called. Unclear if it's still offered in the browser as it seems to have made it's way to Steam.