Merb is a micro-framework (developed by Ezra Zygmuntowicz) that ties in with Mongrel and erb and provides basic controller and view templating. It's an ideal way to put together quick and simple Web applications with Ruby that don't rely on any of the fancier features offered by Rails. It does have support for ActiveRecord, however. Merb allows you to create small systems that produce dynamic requests and can interact with databases but without the significant weight of the Rails framework. Where Ruby on Rails is a Big Mac, Merb is a McNugget.