How big is BIG?

This morning I was looking at the Web site of the Sloan Digital Sky Survey

Fascinating stuff! SDSS is systematically mapping the entire sky, determining the positions, brightnesses and distances of celestial objects, to give a three-dimensional picture of the universe through a volume one hundred times larger than that explored to date.

They are obviously asking some basic questions. And getting answers, too. one question that really tickles my fancy is described in the article How big is big? Probing the conditions of the universe on the largest scales

Back in May 2006 researchers at SDSS announced the first measurements of galactic structures more than a billion light years across. Now that's getting to be sizable, isn't it!