[W]e’ve been having a lot of fun writing a series of small, self-contained web apps .. When we’re building these kinds of applications, which are often meant as low-ceremony apps targeted at a very specific purpose, or as service utilities, a lot of the time we don’t want to go through the hassle associated with a “normal” web app.

Dave Hrycyszyn

In Skinny Daemons, Dave Hrycyszyn presents a practical walkthrough of how he builds what he calls "skinny daemons" - small, HTTP based daemons to perform single tasks that are then packaged up into gems for easy installation (across multiple servers, for example). It's a practical demonstration and holds your hand the whole way. Useful stuff.

An example of a skinny daemon is enigmamachine, a video processor Web service using ffmpeg to convert videos to profiles of your choice.