Moving blocks are normally temporary, and are created when a piston pushes a block. However, they can get stuck as a moving block if the piston is unloaded while the block is still loaded.
Obtaining
Warning: Corruption
This feature can corrupt your world. Perform at your own risk.
This method requires a crash, which could possibly corrupt your world
Using a specific setup, a piston can be timed to push a block and then be unloaded while the block is still moving, causing the block to stay as such. Then, wait for an autosave and crash the game. This method is not consistent, and may not work every time.
A video example for how to perform it.
Trivia
This works with any moveable block, but moving blocks lose their functionality, such as container blocks, redstone components, and rails.
Permanent moving blocks are not entirely relog proof. Occasionally upon relogging they can revert to the normal block, but it is unknown what causes this to happen.
If the piston that originally pushed the block is destroyed, the moving block will revert to normal.
