A disadvantage of brewing tea in a teapot is that the tea leaves can over-steep: If, after pouring the first cup of brewed tea, the tea leaves are still submerged in the hot water, then by the time you pour your second cup the tea will be strong and bitter.
This teapot made by Ronnefeldt, however, solves that problem in an ingenious, out-of-the-box way. For details, see the photo and caption below.
"Put leaves on the shelf (seen through the opening on the teapot to the left), fill with hot water, and lay the teapot on its back. As the tea darkens, tilt the pot. Finally, when brewing is complete, stand the teapot vertically, so the water no longer bathes the leaves and the brew does not become bitter."