Here's an interesting article by jazz pianist and teacher Willie Myette. It's about something called 'quartal harmony' which is just a fancy way of saying how to build chords using 4ths intead of 3rds.
I'm actually a big fan of quartal harmony as it has a very ambivalent sound - which is perfect for the New Age style of piano playing.
Willie has also recorded some examples so you can hear what it sounds like. Your Lesson Five: "Winter Scene" is based on quartal harmony!
I think you'll enjoy this article. Find it at http://jazzpianolessons.com/articles/richer-piano-chord-voicings-with-quartals