When your eyes start to go, you have some satisfying remedies. Glasses — a centuries-old technology that costs a couple hundred bucks and is often covered by health insurance — or contacts, which are constantly improving. But if your hearing starts to fade, get ready for sticker shock and frustration. Hearing aids can cost more than $3,000 apiece, they don't do a good job of correcting the problem, and insurance companies rarely pay for them.
Welcome to the screwy world of ear gear. Because these devices are highly specialized, manufacturers build most of the parts from scratch — their products benefit from neither economies of scale nor third-party innovations. And as a result, there has been little progress in improving three critical components: the microphone, the microprocessor, and the battery.
The woes start with the microphone. Typical hearing aid mics pick up sound from all directions. The resulting cacophony is exhausting for the user, who must concentrate to isolate relevant input. High-end hearing aids add a directional microphone trained in front of the listener, but that increases cost and, critically, bulk.
The microphone feeds a processor, which amplifies certain areas of the audio spectrum according to the user's particular type of hearing loss. But inevitably, some signals recirculate between mic and speaker, producing feedback —

I full heartedly agree with this article. It sums up all of the downfalls of having to wear and maintain a hearing aid including the lovely price tag. :P (This a link off of the "Things That Make Us Crazy" article)