This is fascinating. What do deaf people normally do in lieu of alarm clocks?
So, to answer your question, some [partially] deaf people use a makeshift Arduino robot that is duct taped to the wall next to their bed.
To answer GP's question, some partially deaf people use grumpy significant others as an alarm clock. But I might have to look into a similar robotic setup.
Sometimes it startles me awake, which is an unpleasant feeling, but it works for me all the time. And, given that we have a foam mattress, the buzzing is absorbed enough for my wife to easily sleep through it.
I recently discovered Bellman & Symfon, a Swedish company that has some very attractive (naturally) products. Their vibratating/flashing alarm clocks integrate with wireless smoke detectors. I can easily get a stand-alone strobed smoke detector in just my bedroom, but that doesn't help if the other end of the apartment is in flames. http://www.bellman.com/en/our-solutions/fire-safety-solution...
I've had mine for years; I'm surprised they're still making it - I've gotten used to the 'cult of the new' lifestyle that seems so prevalent. :)
(Anecdotally, I don't actually know any deaf people, so I don't know how effective this is as a way to wake people up...but some of my friends who have perfectly good hearing use this feature because they prefer it to having their phone make loud noises for calls and notifications. So it's good for that, too.)
I believe person who initially showed me this feature kept her phone in a open-top handbag. Again, whatever the phone orientation, the reflected bright notification flickering would often be noticeable.
The notification flashes are somewhat negative distractions in dark places like a car at night, or theater, if the phone has been left on lap or seat. Also, it may sometimes give third parties the mistaken impression you're taking photos when you're not.
http://www.walmart.com/ip/Clarity-Alarm-Clock-With-Bed-Shake...
http://www.amazon.co.uk/s/?ie=UTF8&keywords=alarm+clocks+for...