A practical walkthrough of using map/reduce with MongoDB to aggregate statistics for generating a report.
Sugar augments the existing JavaScript environment with helper methods on existing objects. From fixing broken support of standard methods, widening acceptable arguments, multi-lingual and improved regex support on strings, nice supplementary string methods like words(), and shortcut methods to Math object methods. Additional helpers for Dates, Objects, Functions and Regex. An library for a consistentising JavaScript across different imlementations.
Cory Hudson sees callbacks as benefiting from currying JavaScript functions, and defines currying as turning a function with two arguments into a function with one argument that returns a function of one argument. He starts off with two functions and shows how to combine them into one curried function, and also builds a generic version. He shows a good usage of a curried function in an array map() function, which is similar to Prototype's bind().
Dan Webb describes curried functions as a way of creating reusable callback functions for event handlers or Ajax requests, or anything that takes a function as an argument. By using closures, curried functions have a simple way of persisting data between calls. He also offers an elegant way of running a lots of methods on objects, with a simple map function written as a curried function.