These are all mentioned in the thread the description links to, but I think it's worth pointing theme out as highlights.

Aubrey De Gray on aging http://www.ted.com/index.php/talks/aubrey_de_grey_says_we_ca...

Jeff Hawkins on AI http://www.ted.com/index.php/talks/jeff_hawkins_on_how_brain...

Neil Gershenfeld on Fab Labs http://www.ted.com/index.php/talks/neil_gershenfeld_on_fab_l...

Ray Kurzweil on how technology will transform us http://www.ted.com/index.php/talks/ray_kurzweil_on_how_techn...