LINQ gems: Indexed Select

Here's another LINQ gem, which is very useful if you plan to base your projection or filtering logic on the element's index in a sequence. From the MSDN page for Enumerable.Select(): Projects each element of a sequence into a new form by incorporating the element's index. What the "incorporating the element's index" part means is that you get an extra parameter inside of the Select method's selector, which gets incremented with each processed element. As is common in C#, the index is zero-based.