Remember when Valve used to make new games, instead of just making insanely popular platforms for selling games (and hats and skins)? Valve promised a partial return to those days today with the announcement of a brand-new Portal game... that just so happens to be built as an expansion to Bridge Constructor.
OK, this might not be the Portal sequel that everyone was expecting or hoping for (that would probably require putting a "3" on the game's title, which we all know Valve can't do). Still, the teaser trailer for the Bridge Constructor Portal—being developed alongside Headup Games and Clockstone Software—shows the same kind of physics-based gameplay that has made both Portal and Bridge Constructor into hits with fans of emergent design.
And GLaDOS makes an appearance, too. What more could a Portal fan reasonably want?