I am currently writing a FOSS Rails app and would like to get some ideas about where to promote the application. I am searching for something like opensourcerails.com or wiki.rubyonrails.org/rails/pages/OpenSourceProjects
Put it on github, too - it's social, Rails-oriented and free repos have to be open-source.
Edit: I'd get in touch with the leading blogs about it, then. They'll get word out way faster than if it's simply sitting on a static list of projects.
You could ask the people who do various rails podcasts to give it a mention.
Try finding the people who would benefit from using your application and tell them about it.
Don't promote it as a Rails application. Promote it as an application that solves whatever problem your application is meant to solve. I doubt there are very many people who sit around thinking, "Boy, I'd sure like to run a Rails application. I wonder what app I could run." Rather, they think something like, "Boy, I sure wish there were a FOSS liveblogging app with Twitter integration."
Announce it on the rubyonrails-talk mailing list where people from all around the world subscribe to. From there, if you keep doing good things the word-of-mouth should spread it around.
If we knew what your app did we could be more precise about where to put these kinds of things.
Working With Rails has a showcase section (previously HappyCodr)
http://workingwithrails.com/browse/sites/showcase
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