^ thats a great goal, Its fantastic to see someone so concerned with the welfare of others. I on the other hand do not ever see my self being noble enough to give up 10% of my income to help other people. Honestly I can't see myself giving up any of my income. Though being an electrician I do go do work for charities trying to help low income home-owners, struggling schools, community centers and other such things. While the impact may be the same I just don't really view it as as much of a sacrifice as giving money.
I don't think everyone should do this by any means! It's just one of my goals. I'm not religious at all (weak atheist) but I like the idea of tithing. Also, I grew up in a situation where I learned to be very cheap, because all "gifts" had to be earned. I wasn't just frugal with myself, I was cheap to others, and I didn't like that. This goal is part of getting that out of my system.
Another part of the reason I want to do this is that I can't volunteer. I have depression, which I manage pretty darn well, but it does mean I have to ration my energy. I'm introverted, too, so dealing with people isn't my favorite thing; the wonderful interpersonal dynamics of nonprofit organizations can be brutal. For me, time is a lot more expensive than money. I don't consider money nearly as much of a sacrifice as volunteering!