Agreed, if you don't mind the size or appearance you should be able to build yourself an awesome hearing aid today in no time. Use a good in-ear speaker, a good

Agreed, if you don't mind the size or appearance you should be able to build yourself an awesome hearing aid today in no time. Use a good in-ear speaker, a good mic and an external controller in a box, based on one of the many DSP chips (or just a fast SoC). You could add filters to attenuate/amplify certain frequencies to reduce noise or amplify speech. You could connect it to your phone via bluetooth. You could even add a realtime translator and have your own bablefish!