The TED Talk that got a standing ovation at TEDx Maastricht 2013:
"Doing the Impossible, Swallowing the Sword, Cutting Through Fear"
I regularly get my clients who have confidence issues to watch Amy Cuddy Power Poses and They Work!
To me the talks by Sir Ken Robinson are so important. The need to fix the root problem for all the rest to happen is the key. It has inspired me to work harder to inspire others to achieve their dreams.
I have two favorites--
and Derek Sivers, "How to Start a Movement"
I have many videos that could easily qualify to be "the best," and each of them feature Michael Porter (Harvard Business School). I find his concepts regarding "shared social value" to be very insightful.
I enjoy this one about leaders, followers and building a movement.