git cat-file tag <tag_name>
will give you the actual contents of the file representing this tag (useful unpacked and uncompressed).
Example
$ git init $ touch README $ git add README $ git commit -m 'Initial commit' $ git tag -a foo -m 'Tagging foo' $ git cat-file tag foo object 91654534f5ac138a3adb56a9e6dc3bacae5bae53 type commit tag foo tagger Peter Lundgren < peter@peterlundgren.com > 1369779403 -0400 Tagging foo
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