Sssnake was similar in play to the game centipede with some major differences.  First, the graphics on snake are very weak.  You control an object in the middle of the screen that shoots at objects moving above and below you.  when you are at the top of your box, you can move only left and right and shoot only up.  When you are at the far right or left, you can then move up and down and shoot either right (on the right side) or left (on the left side).  When you are at the bottom of your box, you can move right or left and shoot down.  Your line of fire is blocked by rows of squares which do not move.  Your enemies move in straight lines above or below the box except for the Sssnake which "slithers" around the entire screen including inside of your box.  If the snake hits you, the game is over.  This game is less common, but not a very exciting game, so it usually sells for pretty cheap.