It depends. Do you have access to the area below your intended location for the sound system? If so, wiring can be installed to go from amp to speakers below the floor system. If not, there are many wire organizers available now for computer system set up. Or wire mould...a plastic back and clip on front to hide wires more stylishly.

Example below: The wires need to run up behind the wall to the ceiling (see image below). A return was created between two existing walls (you will need to create two columns) - through which you can run the wires if necessary. The screen is hidden in the beam above the painting. In the foreground of the photo is another "beam" which actually contains the projector. It has an access panel again covered in the mesh and there is a flap that can be removed or opened/closed when the projector is in use. US is way more advanced, so I believe other Houzzers can step in...

This is basic all an effect created through the latest version of projectors. You can visit projectoreviews for all kind of projector solution. They have different kinds of projectors for you.

Art always works .As for what's in for 2015 it only matters if you love what ever it is and are now willing to change it out for what is in vogue next year . Colors for pillows are what I usually use to bring a space up to what,s in but my basic style and design stay the same for a long time.