It's often useful to remove diacritic marks (often called accent marks) from characters. You know: tilde, cédille, umlaut and friends. This means 'é' becomes 'e', 'ü' becomes 'u' or 'à' becomes 'a'. This could be used for indexing or to build simple URLs, for example.
Doing so is not so easy if you don't know the trick. You can play with String.Replace or regular expressions... But do you know .NET 2 has all that is required to make this easier?
In a comment to an old post of mine about URL rewriting, a visitor named Tim has just asked how to solve a problem he was facing with ASP.NET themes and rewriting. The original post was addressing the main problems by using an overload of the RewritePath method introduced by .NET 2. Yet, a simple problem still existed: whenever URL rewriting is used with a URL like ~/somepath/ the theme gets broken because the path to the CSS files and other themed resources (like images) are wrong. The problem here is the trailing slash, which confuses the theme engine. A URL like ~/somepath works fine of course.