Resume Critique/Volunteer Work Question

Posted this in the IB Forum too, but thought this forum may be better for getting some resume advice:

I was wondering if anyone can offer any insight as to how volunteer work abroad, specifically microfinance, is viewed in terms of work experience and what the best way to include it on your resume is.

I graduated from a nontarget (top 30 UG business school), worked as a trading assistant for a BB for a year, and then left to do volunteer work with a microfinance institution in Brazil. I am going to begin looking for a new job in the fall and would like to try and break into either IB or equity research. I know my chances are slim, given that I don´t have top-notch credentials, but I also know that bankers (or just any employers in general) love seeing something different that sets you apart and I am hoping my experience working in Brazil will help out with that.

My resume is below too, if anyone wouldn´t mind offering any tips/criticisms. Any input on what the best way to include volunteer work on a resume is? Did a search and couldn´t find too much.

http://www.razume.com/documents/21933

Thanks!