Many people in the world are visionaries. Many of these are scientists or designers. Some of them are even internationally famous. The TED conferences pull together many of these inspiring individuals and invite them to speak for a short while (usually 6, 12 or 18 minutes) to share "ideas worth spreading".
Although conference itself costs about six grand to attend, videos of the talks are available on YouTube, giving something worthwhile to watch over lunch or dinner, without being so long that you get distracted halfway through.
Most, if not all, of these talks are of really high quality, spoken by individuals near the top of their game. Speakers have included
Bill Gates, the
genius teenager who built a fusion reactor in his basement and
some dutch guy who takes interesting photos of ducks.
However, the TED channel only gets updated every weekday - if you work through the back catalogue of a few thousand videos, that might not even last you through lunch. Thankfully there's TedX as well, videos of TED-style events from around the world. Between all of these, there has to be something for anyone even vaguely intellectual. But if not, then there's at least this one: