One of the most common tasks I've done over the years is just reading a plain text file - whether it's part of a full import process, or a one time job to clean up a file.
With .NET, it's really easy to loop line-by-line through a file. The StreamReader class can read lines, handling all of the nonsense like line break types.
Here's the easiest way to read and handle a text file. There's actually a faster way, File.ReadAllLines, but that doesn't handle large files well. The StreamReader does.