Yup, wow, you have good memory! My idea was with pong, but same concept yes.
My idea was like this..
Code:
if(gametype == objective && if you're spectating)
{
render a small tetris game within the game itself via openGL
}
Sure you can do a browser "theoratically", but it would have to be rendered via OpenGL. I don't think there is any other way to render the browsers. Most of our modern day browsers are rendered via OS specific syntax, but I don't think that same concept could be used to render on top of a game, so it would need to be done in OGL.