5. Let the linear function $y=-\frac{n}{n+1} x+\frac{\sqrt{2}}{n+1}(n$ be a positive integer) intersect the $x$-axis and $y$-axis to form a triangle with area $S_{n}$. Find the value of $S_{1}+S_{2}+\cdots+S_{2006}$.
(Hint: $S_{n}=\frac{1}{n}-\frac{1}{n+1}$. Answer: $\frac{2006}{2007}$.)
