I am pretty sick of killer apps and the discussions about them, but make
sure you checkout Rails.
Rails is an open source web-application framework for Ruby. It ships with
an answer for every letter in MVC: Action Pack for the Controller and View,
Active Record for the Model.
Everything needed to build real-world applications in less lines of code
than other frameworks spend setting up their XML configuration files. Like
Basecamp, which was launched after 4 KLOCs and two months of developement
by a single programmer.
Enjoy the Show, dont tell! 10 minute setup video (22MB).
Have fun with Ruby .. says a tired Armin right now coding simple cgi-stuff
without any frameworks :-)