Researchers at Hong Kong Polytechnic University have developed ultrasonically-enabled glasses and shoes designed to give the blind a set of "bat ears" that can detect obstacles and report them using varying levels of vibration. From the article: "The shoes will be able to detect steps, holes in the road and obstacles within a five cm (two inch) vertical distance." One independent opinion, also from the article: "There are so many bumps in Hong Kong's road. If I wear the shoes I will end up shaking and vibrating all day."
Using technology to improve our senses is a time-honored activity: binoculars, microscopes, false-color imaging, RADAR, SONAR--all of these augment our sensorium in one way or another. What's interesting here is the attempt to make the technology permanent: always on, always with you (shoes and glasses might come off only at night) and so intimate that it ultimately disappears (assuming it doesn't shake your fillings out first). I've speculated about permanent sensorium enhancers; here are a few "extra-sensory" phenomena I wish I could detect more or less continuously: Lies, weather (with greater accuracy than my naked eyeball supplies), the criminal records of people near me (particularly those following me), North (so I can stay oriented as I flee the five-time offender) and calories (especially in restaurant food, which is often deceptive). Possible augmentations from the cyber world: my mail queue (don't laugh: I saw a guy in a Men's room once checking e-mail--he'd probably love a continuous queue view); my IM buddy list; and possibly a CNN feed so I can track the state of the world.
ESP of this sort poses interesting UI challenges--there would be a lot of data competing for your attention, and there's a very real risk that you'd suffer sensory overload. Some of the data might come in visually (imagine HUD glasses); some might be audio (trusty Bluetooth headset); some (such as North, calories and lies) might be delivered through a vibrating watch or belt. We'd need a new word something like "blind" to describe how you feel when your artificial sensorium crashes, and of course it would be irresistable to crackers ("You're all lying! And the Sun rises in the South!"). But you'd tend to operate as if that could never happen. After all, if you can't trust your senses, what can you trust?