LINQ

Extending LINQ with Random Operations
You can create extension methods to extend LINQ. Here's some code I came up with for extending LINQ to return random list items and shuffle lists.
By Jonathan Wood on Saturday, September 22, 2012

Extending System.String
Using extension methods, it is easy to extend an existing class. Here's some code to add a number of interesting extensions to System.String.
By Jonathan Wood on Friday, July 11, 2014

Implementing The TakeLast, TakeLastWhile, SkipLast And SkipLastWhile LINQ Operators
Some time ago, I needed to retrieve the last items of a sequence that satisfied some criteria and, looking at the operators available in the Enumerable class, I noticed that there wasn’t such an operator.
By Paulo Morgado on Wednesday, February 9, 2011