Get Mars Tracks:
After pausing the game press Left, Left, Right, Right, Left, Left, Right, Right, Down, Left, Right

Get Wide Angle Mode:
After pausing the game press Left, Left, Left, Right, Right, Right, Up, Up, Up, Down, Down, Down, Left, Left, Left, Right, Right, Right

Get Martian:
At the main menu press Right, Left, Right, Up, Down, Left, Right, Up, Up