Here is a quick video of the guys scraping our ceiling when we remodeled about four years ago. sstrams described it exactly right, and pointed you to a scraper. He is also correct that it makes a huge mess, so if you're not replacing the flooring you'll want some decent plastic over it. Otherwise, it's pretty easy.
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1drv.ms]
Hope the link works...
Aries
~Sign of the Rams
