Another gem from Daniel Hölbling.

In short – it will allow you to write code like:

public void Browse([DefaultValue("beer")] string category, [DefaultValue(1)] int page)  {  
   ...
}

grab it here

The cool thing is that because MonoRail is so extremely flexible, one can really easily add this type of functionality without touching the code-base, but rather implementing a straightforward interface. That’s what I call extensibility.

One more super kudos to Hammett for the overall architecture of MonoRail.