The folks at Intridea have been coding up a storm!
In time for this week's Railsconf, they are rolling out a hosted, on-demand version of their popular Scalr tool, a new release of their MediaPlug media server appliance, and the Acts as Community social network.
Scalr gives enterprise IT professionals the ability to quickly and easily set up and run EC2-powered server farms. Once such a farm has been set up, Scalr monitors and maintains it, with automatic scaling, failover, and redundancy. Scaling is based on load averages, with automatic instantiation of new instances of the proper type once the aggregate load average reaches a configurable threshold. If an instance crashes, Scalr replaces it with a new instance of the proper type. The hosted version is available for $50 per month; the open source version can be downloaded here.
Finally, Acts As Community, is a social network for Ruby developers. Of course, the site runs on Amazon EC2 and is managed by Scalr. The site includes forums and blogs for open source projects hosted at GitHub; user group creation and management tools, personal profiles, and a number of community features such as forums, questions and answers, media sharing, and code sharing.