Of course almost all TED talks are worth noting, but three are particularly rocking. The first two are by Aimee Mullins. The first is more of a show and tell Q&A session, discussing the various legs she has and the stories behind them. The second is a formal talk with an interesting story about her interactions with children.
The third video, featuring Pattie Maes, discusses what her lab calls a "sixth sense" - a combination camera and projector system and is location and context aware. If you've seen some of the MIT 'cyborg' types before, think of this as the iPod-ization of that concept. Though I don't really consider this a new 'sensory' experience, the demo is pretty amazing.