Let $ABC$ be a right angle triangle with $BC = AC =1$. let $P$ be any point on $AB$. Draw perpendiculars $PQ$ and $PR$ on $AC$ and $BC$ respectively from $P$. Define $M$ to be the maximum of the areas of $BPR$, $APQ$ and $PQCR$. Find the minimum possible value of $M$.
Hint is appreciated.