Ruby for the Server, and Maybe the Web Too.
With the onslaught of Ruby on Rails people tend to forget that ruby is actually a Turing-Complete language, meaning it can do anything. With the standard library and RubyGems you can do some really cool server side "stuff" to make life a bit easier. You will learn about a couple of the Ruby implementations as well as how you can use them on the server to enhance your productivity, and make doing support and development a tad bit easier.