Twgit is a free and open source assisting tools for managing features, hotfixes and releases on Git repositories. It provides simple, high-level commands to adopt the branching model describes in our documentation. Supported OS: Debian/Ubuntu Linux, Mac OS X 10.8 (Mountain Lion) or lower.
For example:
$ twgit features list [--author|committer=<pattern>]
(thx to Amin for idea)