Ok, this is just a really simple little demo. And you might be thinking that it's not really doing anything special because it's still on the domain and we can do whatever we want. Technically you're correct but to prove nothing special is going on you can copy and paste the following code into either an existing page or a new page on your website and it'll work exactly like it works here.

Here's the working demo:

Here's what you can copy and paste into your own site:
<script language="javascript" src=""></script>

<input type="text" name="zip" id="zip" value="92806" /> 

<select name="radius" id="radius">
	<option value="1">1 mile</option>
	<option value="5">5 miles</option>
	<option value="10">10 miles</option>
	<option value="50">50 miles</option>

<input type="button" value="Search" onclick="searchZip('zip', 'radius', 'results');" /><br /><br />

<div id="results"></div>

Simple enough, right? That's a working demo of the front of the system. You can demo the management interface here.