I am always searching for good ST3 packages.
My Idea is that you say the name of your favorite package and then write a very short description about it.
I start with Emmet.
With Emmet you can write little snippet's like this(I know this isn't ):
html:5>(div.nav>ul.nav>li.nav*4>a[href="#"]{$})+(div.content>h1{Hello World}>div.posts>div.post*2>h3.post+p.post>lorem)+(div.footer>p.footer{Copyleft})
And Emmet "transforms" it into this:
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Document</title>
</head>
<body>
<div class="nav">
<ul class="nav">
<li class="nav"><a href="#">1</a></li>
<li class="nav"><a href="#">2</a></li>
<li class="nav"><a href="#">3</a></li>
<li class="nav"><a href="#">4</a></li>
</ul>
</div>
<div class="content">
<h1>Hello World
<div class="posts">
<div class="post">
<h3 class="post"></h3>
<p class="post">Lorem ipsum dolor sit amet, consectetur adipisicing elit. Nobis enim nesciunt, impedit esse doloremque. Ipsum aspernatur quae, exercitationem, neque expedita earum dolorem officia illo placeat culpa reprehenderit minima laboriosam recusandae.</p>
</div>
<div class="post">
<h3 class="post"></h3>
<p class="post">Eligendi dolorum, maiores officia saepe libero, nam nostrum nesciunt, dolorem impedit cupiditate id debitis? Blanditiis recusandae necessitatibus, iure consequatur perspiciatis. Quasi labore vel, impedit cupiditate temporibus nostrum explicabo omnis ex.</p>
</div>
</div>
</h1>
</div>
<div class="footer">
<p class="footer">Copyleft</p>
</div>
</body>
</html>