It's not only the presence of the Colossal Titan in the show Attack On Titan that fascinates viewers, the speedy 3D Maneuver gear action by the Scouting Legions also draws people to the series. A Japanese freelance engineer who is famous for creating a series of Puella Magi Madoka Magica web mini-games made an unofficial Attack On Titan mini-game called "Susume! Rittai Kidou! (rough translation, Let's Go! 3D Maneuver Gear!)".
You can play it on internet for free, either on PC or on smartphone. When the red letters on the top page says ready, you can click or touch on the panel to start the game. It can also be played on the Wii U's GamePad through the Internet Browser.
The object of the game is to keep moving forward as far as you can while either to avoid or to attack the back of the neck of the Titans that appear every 200m.
Shoot the wire by a click or a touch and hold on smartphones. The angle and the length of the wires depends on how you click / touch and hold and when you let go. The gas gauge is at the top indicating how much gas is left after using it to retrieve the wires. Gas is recharged every time you are on the ground running. Occasionally, potatoes show up for a full tank of gas for 10 seconds.
I tried it on my laptop and on my iPhone. It's very simple, yet surprisingly enjoyable. The creator of the game suggests playing the OP "Guren No Yumiya" while playing the game and the Netlab author suggests screaming "Jaegerrrrrr!" at the right timing for more fun. I haven't screamed "Jaeger!" but I have a feeling that soon I will.