While browsing through the book Presence: An Exploration of Profound Change in People, Organizations, and Society, I came across a fascinating study of how human thought can affect the shape of water crystals. Japanese researcher Masaru Emoto claims that human vibrational energy, thoughts, words and music affect the molecular structure of water. He proves this through beautiful experiments where water, thus affected by thought, is frozen and the resultant crystals photographed under a microscope. The results are spell-binding.
However the Wikipedia entry for Mr. Emoto urges caution on the grounds that his research has neither been published through peer review in academic journals and nor does it follow double-blind procedures.
Something fascinating, albeit to be taken with a pinch of salt.