i have a small gap under the baseboards that you cant see because the carpet, and i run my wires under them. When people come over, they ask me if my equipment is wireless because you cant see a single cable anywhere, it just looks like speakers sitting there not connected.

In my old house, i didnt have that luxury, so i used those little wire clamps you can nail into the wall and ran them along the bassboards, and then around the doorframe. its time consumning but it doesnt look all that bad, especially if you can find white speaker wire and clamps to blend in.