Gemcutter
Well, if you work with ruby and rails and you do not know what Gemcutter is then its time for you to come out of the rock you have been living under. It is the awesome gem hosting service that has in time replaced rubyforge for good.
And, now I am an official contributor to such a incredible application. Yes, I added a feature in and it has been merged into the main production branch due for release very soon. And, I am now sitting along the likes of Jim Weirich in the contributors list. Awesome.