Attention Ruby on Rails fans, 37 Signals — the folks who created Ruby on Rails — have put together a new, configuration-free, version of Rack for OS X, the Ruby web server interface. Pow, as the new tool is know, allows you to install and run Ruby apps on your local machine without fiddling with Apache config files or setting up virtual hosts. It just works.
Pow is a Node.js app written in CoffeeScript. It includes an HTTP and a DNS server and runs Rack apps through the Nack library. For some more background on Pow, check out this screencast, which covers the internal workings of Pow, along with some of the motivation behind it.
Some commenters on Hacker News have expressed concern that Pow’s installation process consists of running a shell script from a remote server — simple and fast to be sure, but potentially vulnerable. If that bothers you than Pow is not for you.