Zen is about simply "being".  It is not so much a branch of philosophy, but a way of existing and accepting the presence of your consciousness.  It is about simplifying everything; the chaotic, entropic world of biological clutter and the inevitable tendency of randomness.  Its often equated with minimalism, and I believe that this is for a valid reason.  If we eliminate all unnecessary sensation from our lives, we can exist without any chemical addictions and then appreciate our naked essence.  Zen is not really modern though.  Its been around for a very long time and is rooted in traditional Japanese culture.  More recently, it has been adapted to the Californian, organic, free-trade, Prius-driving, pot smoking yuppie.