title: Best GUI control(s) to describe a time range
body: <p>I need to let end users specify a time range, to be stored and used internally as a starting date/time and ending date/time.  The range could be minutes or it could be days.</p>
  
  <p><strong>Has anyone discovered an interactive control that can handle this elegantly?</strong></p>
  
  <p>Most GUI toolkits have a calendar control, so I could specify "start" with a calendar for the day and a text field for the time...and the same for "end".</p>
  
  <p>I could also replace the "end" controls with a single text field or slider that simply describes how many seconds/minutes/hours after start "end" is.</p>
  
  <p>What I don't like about these ideas is how much clicking, typing, and more clicking is required to describe such a simple concept.  Also I have to slap the user's hand if a time is typed in that isn't recognizable as a time.</p>
  
  <p>Is there a cleaner implementation that I'm overlooking?</p>