title: Remove everything that is not a email adress with Regex
body: <p>I have lines that contain email adresses and hidden variations of email adresses, for example, use of <code>[at]</code> instead of <code>@</code>. I would like clean this list from everything that is not a email adress. </p>
  
  <p>The TLDs is <code>.com</code>, <code>.us</code> and <code>.me</code></p>
  
  <p>Sample input</p>
  
  <pre><code>johndoe@example.com
  johndoe @example.us
  contant johndoe @ example . me
  my email is johndoe@example.com
  johndoe@example.com is my email
  this johndoe @ example.com is my mail
  johndoe[at]example.com 
  my email is johndoe [at] example.com
  johndoe[at-sign]example.com
  johndoe at example.com
  johndoe[at-sign]example[dot]com is my mail
  Lorem ipsum dolor sit amet, consectetur adipisicing elit, johndoe[at-sign]example[dot]us 
  johndoe[at-sign]example[dot]me labore et dolore magna aliqua
  Sed do eiusmod tempor incididunt johndoe at example dot com
  Duis aute irure dolor in reprehenderit in voluptate  JOHNDOE at EXAMPLE dot US aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur
  Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum johndoe at example dot me
  </code></pre>
  
  <p>I am using Notepad++ search and replace and my try is this <code>[\w]+(|\s)(@|at|\[at\]|\[at-sign\])(|\s)[\w]+(|\s)(\.|dot)(|\s)(com|us|me)</code> and it seem to work on everything but not line 11, 12, 13 and 15. </p>
  
  <p>Wrote this on my own and, is this the right way?</p>
  
  <p>Desired output:</p>
  
  <pre><code>johndoe@example.com
  johndoe@example.us
  johndoe @ example . me
  johndoe@example.com
  johndoe@example.com
  johndoe@example.com
  johndoe[at]example.com 
  johndoe [at] example.com
  johndoe[at-sign]example.com
  johndoe [at-sign] example.com
  johndoe[at-sign]example[dot]com
  johndoe[at-sign]example[dot]us 
  johndoe[at-sign]example[dot]me
  johndoe at example dot com
  JOHNDOE at EXAMPLE dot US
  johndoe at exampledotme
  </code></pre>
  
  <p>I don't expect this to be 100% bulletproof since I have read that <a href="http://www.regular-expressions.info/email.html" rel="nofollow">e-mail validation can be hard</a>. </p>