Learn some basic voice production for stage techniques. How your voice sounds is an absurdly strongly weighted component of a first impression, particularly over a phone or prior to direct introduction, and being able to project your voice in a commanding fashion has an overpowered influence on how much people listen to you and consider you a 'natural leader.' In particular, learn what it means to speak from the diaphragm, and learn some basic exercises for strengthening your subsidiary vocal chords like Khargyraa and basic tuvan throat singing, and you'll be surprised at how much it makes people sit up and listen. You might coincidentally have your voice drop into a lower register after about a month of such exercises, it (anecdatally) happened to me and several people in my voice production for stage class in college. (class of 25, 6 people had their voices drop within the first 4 months, teacher said those numbers were normal.)
Most people just assume you're born with a voice and have to deal with it, which is demonstrably untrue, and so they consider your voice to reflect your character.
This is cool! -- but how does being able to do it make a difference when you're speaking normally? (Other than the voice-lowering thing you mentioned.)
While I'm asking questions: Did you or any of your classmates find it did long-term harm to the high singing voice? (I'm specifically interested in the male voice just below the break.)
Thus spake Eliezer:
It seems that many here might have outlandish ideas for ways of improving our lives. For instance, a recent post advocated installing really bright lights as a way to boost alertness and productivity. We should not adopt such hacks into our dogma until we're pretty sure they work; however, one way of knowing whether a crazy idea works is to try implementing it, and you may have more ideas than you're planning to implement.
So: please post all such lifehack ideas! Even if you haven't tried them, even if they seem unlikely to work. Post them separately, unless some other way would be more appropriate. If you've tried some idea and it hasn't worked, it would be useful to post that too.