Considered the founder of video art, Nam June Paik, has an incredible body of work.  Originally inspired by the Fluxus movement, Nam went on to create a new genre and developed the community of performance and conceptual thinkers that sprung out of the 60s and 70s.  He has used TVs and lighting to create installation work that is breathe-taking.  His collaboration with and inspiration on other artists is moving to me.

images and info found from wikipedia