My brother Jason (who's studying product design at Stanford) sent me a link to this design of a "hearing impaired home sensory device." It's a bracelet that presses different pressure patterns onto your wrist to tell you that your phone or doorbell or whatever is ringing.
It's also very obviously a 3D mockup that's almost certainly never actually had a working prototype constructed - or rather, I'd be impressed if it were made, because... okay, you're talking wireless receptors here, right? The bracelet has to get signals from somewhere. How do you install this transmitter on your alarm clock/doorbell/phone? All right, say all these things (miraculously, somehow) have, say, Bluetooth; that might be marginally reasonable. What's its range? Bluetooth is about 10 meters (100 meters with a Class 1 transmitter, which pumps out 100mW) but still needs line of sight; walk behind a wall and you're done for, and I'm assuming people like living in houses with walls, and occasionally also want to leave said house.
There are longer-range protocols that go through walls, but then you've got to make your doorbell all hooked up to that protocol, and even before you think about that, just think about power, because seriously - continuously operating wireless and small lightweight quiet (so maybe they exist, but even if they do, how much would they cost?) actuators of that size in a bracelet that thin with sufficient travel distance (mechEs, what's the word I'm looking for?) and force to put pressure on wrists of wildly varying circumference and how does this not run out of battery within 5 minutes?
There is one thing I like about it, though. The first commenter said that the designer "should have gained a better knowledge of the incredible number of items already designed to provide and promote communication and access between and for the deaf and hearing impaired community." There are flashing doorbells and such. I don't have them. Part of the reason is that I'm still moving around a lot, part of the reason is that I don't need to be alert for visitors at all times, and part of the reason is that flashing lights are Giant Hello I Am Deaf signs. A bracelet wouldn't necessarily mark me as such.
Then again, I don't wear jewelry.