July 22, 2009 This article was contributed by Valerie Aurora You probably have heard of the cool new kid on the file system block, btrfs (pronounced "butter-eff-ess") - after all, Linus Torvalds is using it as his root file system on one of his laptops. But you might not know much about it beyond a few high-level keywords - copy-on-write, checksums, writable snapshots - and a few sensational rumor