Erek Tinker wow, it sounds like a fascinating area of study!
  Let's see: I believe it creates an awful lot of the oxygen we
  breath... it's used as a thickener in milkeshakes and in other
  food products... hmm... here in Florida we have problems with
  Red Tide: Nitrogen that makes our plants grow GREAT *also* feeds
  the red algae, causing it to grow in excess. (also phospherous
  but that's been known ...for years, and the reason why it was
  taken out of automatic dishwashing detergent, making it work
  HORRIBLY now (just add a little TSP from the hardware store to
  get the cleaning power back)...."