Salt includes a number of built-in external pillars, listed at Full list of builtin pillar modules.
You may also wish to look at the standard pillar documentation, at Pillar Configuration
The source for the built-in Salt pillars can be found here: https://github.com/saltstack/salt/blob/develop/salt/pillar
Docs for previous releases are available on salt.rtfd.org.
Latest Salt release: 2014.7.2
22.21. Full list of builtin pillar modules
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