Select unit / menu option: Enter
Unselect unit / menu option: Escape
Tilt camera: click-and-drag up/down with right mouse button
Zoom in/out: mouse wheel, or PageUp / PageDown
Rotate map 45 degrees: left or right brackets [], or Home / End, or click-and-drag left/right with right mouse button
Reset camera to default view: R
Forfeit current scenario: W
Show frames per second: F
Toggle all sounds and music on/off: S
Toggle full-screen mode: F12 (Linux only.)
Dump current map file to console: ScrollLock (this is useful if you find a good random map, and want to save it.)