Solving difficult binary puzzles

Sometimes rather difficult steps are required to solve the most difficult binary puzzles. Consider for example the blue cell in the puzzle below. Do you see which number should be placed here?

Especially for starting binary puzzlers this is not easy to see. We will give a step by step explanation.

Two zeros and two ones are missing in the fifth row. Because at most two equal numbers are allowed to be placed next to each other, there are four possibilities for the fifth row:

Because each row of the puzzle has to be unique, and because the second possibility above is equivalent to the second row of the puzzle, this possibility can be crossed out. The three remaining possibilities for the fifth row are:

Maybe it's already clear now which number has to be placed in the blue cell. Regardless of the possibility we choose, there will always be a one in the fourth cell of the fifth row. We can thus fill in a one in the blue cell.