I'm the ONE!!

I don't know about the rest of you, but I find it so frustrating trying to prove to people who don't know me that I am what they are looking for!
Odds are that you've got no idea what I'm talking about. 
Recently I experienced an epiphany. I heard nightingales with the sweetest melody in the background, and saw a gloriously bright light in the foreground, and after it passed everything seemed so clear!
I discovered my dream job, my career, my calling in life. Soon after I browsed to my calling in life's website, and began the online application procedure. I was applying for something in the humanitarian field. On the application form the final question, to be answered in no less than 400 words, is this: 
Why do you want to work in the humanitarian field?


Honestly, I was stumped. I had to write something that wouldn't sound too dramatic, and wouldn't give the impression that I was a care bear in disguise. At the same time, it had to convey without doubt that I understood and valued humanitarian work, and would be committed and devoted to it. So far so good right? Manageable. But to actually accomplish both previous points, AND manage to say something that the thousands of applicants on this site hadn't already said? Not so manageable. 
I want to make a difference, change the world! I feel the highest level of satisfaction when helping others! I don't like what the wold is coming to, and I want to take a stand for the better. I know there is a lot of suffering out there, and I would like to do my small part in alleviating it. So on and so forth...


Seriously, think about it! When applying for your masters at some esteemed university and are asked "why are you applying to XYZ university?", how many truly unique answers to this question are there?
The same logic applies to any interview question or application. So here's my question. What can I do to make the recruiters at the organization I'm applying to see that I'm the ONE! (Because I so totally AM!!)


Wanting to make the perfect impression and answer in the best way possible, I turned to research. I checked online articles and even read some best-selling books about how to answer interview questions. They give you great tips, like how to downplay your weaknesses while being honest about them, or how to be diplomatic when talking about your previous job and reason for leaving... But then again, how many of us have read these books/articles? Following the advice in them might help get a proper answer, but not a unique one that helps to stand out between the hoards of other applicants. 


So I answered the essay question on the online application I was filling. I tried to make my answer as personal as possible, so that reading my 400+ words would be like a small introduction to who I am. I gave it my best shot. But I can't help thinking that my application just won't stand out. I haven't said anything that at least a hundred others haven't said in their own words.