At the beginning of this year we finished work on a screened porch for our house. It is something we had been thinking about for as long as we've owned the house (which for the record has been about a decade). The house had an existing back porch but after we demolished it we made the counterintuitive decision to make the new porch smaller in order to make it more functional. By pulling one side away from the house, prevailing breezes could more effectively flow through and cool the space. The addition of a built-in concrete bench and a hammock ensured that the space could be used throughout the year. The lines of the original house were maintained so that the addition felt like an integral part of the original structure.
We've been using the screened porch quite a bit for outdoor meals, birthday parties and simple relaxation. We've also used it in ways we could have never imagined.