title: Best email validation function in general and specific (college domain)?
body: <p>I know email validation is one of those things which is not the funniest thing on the block. I'm starting up a website and i want to limit my audience to only the people in my college and i also want a preferred email address for my user. So this is a two part question.</p>
  <ol>
  <li><p>Is there a really solid php function out there for email validation?</p>
  </li>
  <li><p>Can I validate an email from a specific domain. I dont want to just check if the domain exists, because I know  <a href="http://www.mycollege.edu" rel="nofollow noreferrer">www.mycollege.edu</a> exists already. Is there really anyway to validate that the user has a valid @mycollege.edu web address?</p>
  </li>
  </ol>