title: JavaScript/jQuery String Replace With Regex
body: <p>Let's say I retrieve the value of a <code>&lt;textarea&gt;</code> using jQuery. How can I then replace a portion of the value using JavaScript/jQuery. For example:</p>
  
  <p>string: <code>"Hey I'm $$zach$$"</code></p>
  
  <p>replace <code>$$zach$$</code> with <code>&lt;i&gt;Zach&lt;/i&gt;</code></p>
  
  <p>And still keep the rest of the string intact?</p>