Elimination Communication - also known as Infant Potty Training, Natural Infant Hygiene, or just "how we deal with pee and poop" in various countries around the world like India and China - is a method of dealing with baby's pee and poop without (exclusive) reliance on diapers. We didn't use this at all with Liam but we have been "ECing" with Del since he was 2 days old, focusing on poops and letting him pee in his gDiapers if we don't put him on the potty often enough (which is difficult with a newborn - he is 8 weeks old as I type this and Daddy Garvin is holding him on a potty at the moment). The basic premise is that babies are as capable of communicating their need to eliminate (poop or pee tho poop is generally easier to spot the cues - grimacing and grunting in most cases) as much as they are able to communicate their other needs such as to breastfeed. As any experienced breastfeeder will tell you, babies do NOT need to cry to make their desire to nurse obvious, and neither do they need to cry to make their need for a potty obvious.
More to come when I get around to it ;)