There are multiple ways to get the source code for blender. If you are going to actually try to use the source code you should really use Git to checkout the latest version. If this is of interest to you, see our getting involved with development section.
Download the md5sum to the same directory as the source tarball and run the following command to verify the integrity of the download.$ md5sum -c blender-2.78a.tar.gz.md5sum
Do you like the taste of danger in the morning? We've got exactly what you need, daily builds.
Discover the latest features, often undocumented, unstable, and full of surprises. There might be cool bug fixes too, but we do not recommend to use this builds on production environments though. These are automatically built on our servers just like regular stable releases, but instead they use the latest snippets of magic code developers write. Every single day.