I am a huge TED fan.
TED is a small nonprofit organisation devoted to Ideas Worth Spreading. On the site you’ll find a collection of videos of people who speak at the TED conferences held around the world through out the year. These people share their innovative, creative thoughts, inspiring ideas, knowledge, skills and experiences. On the site you will find a collection of videos lasting from a few minutes to ~20 minutes in length. The topics cover technology, science, the arts, education, politics, business, design, the environment and everything in between. The speakers have been selected for their ability to communicate effectively and succinctly, more often than not they are also entertaining and funny.
If you have not ever been to the site yourself do yourself a favour GO NOW.