I like things to be as direct as possible, so I tend to like small, very hands-on orgs with minimal if any administrative costs, like my local Womens' Shelter, or individuals who dedicate themselves to easing the suffering that is all around them. That's how Common Ground in New Orleans started!
Of the larger national orgs, I like Dress for Success, and of the mega-orgs, as you can see in my sig, I really like OxFam's gift program.
Even though OXFam is huge, the focus of the gift program is local and direct. Family needs goat, family gets goat!
Ideally, though, an org shouldn't be necessary.
There is no shortage of need all around me, It is up to me to take the time to notice it and address it as much as is possible within my means. I'm poor, but there are plenty of people who are poorer!