[edited again(June08) and changed for clarification]
When you try to hear better, while your phone is on "speaker", you bring up the volume. But at some point, usually at full volume, the quality of the voice somehow seems ruined, and you gotta bring the volume down so you understand what is said. This
is common. Anyone who understands how sound is produced, understands that what is happening is called "clipping". But this can be fixed, or at least improved using digital signal processing. (See links).
So you can with this halfdea, put your speakers to full volume, and still hear crystal clear.
Here's the original text of the idea:
Make the full-volume speakerphone sound clear, without the "clipping" of voices. It can be easily be achieved thru digital processing, so that when you put your speaker-phone to full volume, it will actually sound good, and still be useful against the surrounding noise.
Technical notes: It could be accomplished by adding software-only or a software/hardware component to cellular phones. The algorithm should be one that maximizes the energy but keeps the phonetics. So sounds like S and V will be simply magnified, but sounds like M and R would have to be modified so that you still percieve the original phoneme but never have the sound clipped.