I love blacksmith, it's great. It does require the forge password be known to the person running it, however.
You can "level up" your deployments to allow others with write access to your repo, but not the forge credentials, in a mature pipeline with Travis CI's
automated deployments. Details on
puppetforge deploys, and an example of
a working .travis.yml (the secure string is generated by
travis encrypt). This allows any contributor to create a tag (usually with
the voxpupuli-release gem and `rake travis_release`, but also by creating a tag on GitHub). Travis kicks off a build on the tag, and if the test specified in the deploy section goes green, your module is published to the forge. That might be overkill for a module maintained by one person, but it is pretty neat when you have a distributed team and can't/don't want to share the forge password with everyone.
I'm sure you could get the same thing working with other services than GitHub/Travis CI, those are just the pair I know.