At West Coast Green, we had the opportunity to chat with the people at Velux. They produce Sun Tunnel Skylights -- a tubular skylight that can bring sunlight into poorly lit places like closets, hallways, small bathrooms, etc.
The people at Velux assured us that installation of a Sun Tunnel is very quick and simple (as opposed to a traditional skylight). According to this article in Popular Mechanics, a Sun Tunnel can be installed by an "experienced person" in about 3 hours, without significantly disturbing your existing roofing.
We love the idea of using sunlight in the home as opposed to artificial light -- it's healthier and obviously uses less energy. According to the Velux web site, electric lighting accounts for one-fifth of the total electrical energy used in the U.S. We wonder how much of that energy is being used during daylight hours?