The game I played most this past weekend is a surprisingly deep one-button RTS called Pax Britannica. To give you an idea of what the game is about, I’ve recorded a short video showing a play session and explaining the mechanics and dynamics of the game.
The game supports 1 to 4 players, and I highly recommend trying it with friends! The nice thing about a one-button game is that it can easily accommodate 4 players on a single keyboard. In addition the game supports up to four gamepads.
(As an aside: what do you think about these video reviews? Do you like the format? Should I do more of these?)