And now for something completely different.
The recent introduction of the ClickStack architecture in CloudBees has opened up the possibility for many novel usages. Most of these so far have been around various JVM frameworks.
Why node.js? well it is so hot right now - node.js seems quite lite on memory usage - and quick to start - you can see how it is done with the clickstack here.
Of course - we have previously, on many occasions, declared out undying love for Erlang - we use it heavily ourselves - so we thought we would expose it for others to kick around a bit. The Webmachine framework from Basho is quite interesting - a very scalable but light RESTful framework for Erlang apps. Basho also make the popular Riak NoSQL database - which webmachine is extracted from. See how the clickstack was done here.
The above are 2 very different but interesting approaches to scalable webapps that address concurrency in different ways. Both make use of Jenkins DEV@cloud service for continuous deployment.
Give them a try.