title: How to implement in-memory logger for last 100 log lines?
body: <p>How to make efficient in-memory log that stores only last 100 entries and <em>can quickly output resulting string to TextBox (on every update)</em>?</p>
  
  <p>I'm doing actual logging to text files using <code>File.AppendAllText</code> but want to have ability to view last entries in my application.</p>