One simple piece of advice: use speaker wire color that's compatible with your room/carpet color. In some cases this makes a huge difference.
For example my HT room is very darkly colored, with almost black carpet. Initially I tried 14-ga clear insulated wire -- the bright copper color stood out like crazy, even for short runs to the main speakers. Then got some black speaker wire from Radio Shack, and it's almost invisible against the dark carpet.
I've seen white, black, clear (copper), and tan colored speaker wire. Maybe other colors exist. If you can get a fairly close match to your room/carpet color, it's like camouflage -- it's there but your eye just passes over it.
For Ajax's run up the wall I don't think that would be sufficient, but IMO for baseboard runs it can make a big difference.
