This contraption is a fan that propelled by magnets repelling each other.
Step 1: The Frame
1) Build a tall wall out of 2x4 brick pieces that is 12 bricks high.
2) Put 2 1x4 brick with 3 peg holes as the 13th brick as seen in the first picture.
3) Stack 12 more 2x4 bricks on top of the bricks with the 3 pegs for a total of a 25 brick tall frame.
4) Repeat step 1-3 to end up with 2 frames as seen in the second picture.
Step 2: The Fan
1) Take 2 1x12 slim pieces and put them on opposite ends of the cross piece.
2) Stick a 9.5cm technic axle through the fan.
3) Add small a technic bush piece on both ends of the axle fairly close to the blade to keep it in place but not touching to prevent any friction.
4) Tape or glue magnet to the end of the blades. Have the North side be facing outwards.
Step 3: The Top
1) Put the 2 2x12 slim pieces next to each other, in the middle, and on top of the 4x10 slim piece. (I added décor on top. Optional)
2) Fill the bottom so it is flush. It should be 2 slim bricks tall at this step.
3) Place 2 1x10 slim pieces under the entire piece so that it is parallel with the 2x12 slim pieces. At this point, the entire piece should be 3 slim bricks tall.
4) Put an 2x2 inverted slope piece in between the 2 1X10 slim pieces.
5) Tape or glue a magnet with South side facing the brick and North touching the tape.
Step 4: Put It All Together
1) Put the fan through the middle hole of the 2 frames and put a technic bush at the end of the axle to hold it in place.
2) Put the entire piece onto a base with 6 pegs in between the frames.
3) Put the top piece on and you're finished!