There is a directory of government agencies using Twitter: GovTwit and you can, of course, follow GovTwit on Twitter: twitter.com/GovTwit.
Mission:
“Looking for government agencies using Twitter or other social media? We want the GovTwit directory to include all facets of government on Twitter: state and local, federal, contractors, reporters, academics and more. The list will be a living list, and we hope to keep it updated via our own research, as well as your submissions….”
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