Edit in JSFiddle

// Nope, no js needed for this one! Just head over to the CSS or Final result. 

<section>
    <button class="noise">Click Me!</button>
</section>

/**
 * A Cool CSS only button with noise!
 */

body{ background: #bada55; text-align: center;}
 
 section{
 margin: 25px auto;
 width: 500px;
}
 
 button {
 padding: 10px 35px;
 border: 1px solid #c97b3d;
 font-family: open sans, arial;
 font-size: 22px;
 border-radius: 15px;
 font-weight: 800;
  background-color: #ef944b;
  background-image: -webkit-gradient(linear, left top, left bottom, from(#ef944b), to(#e67519)); /* Saf4+, Chrome */
  background-image: -webkit-linear-gradient(top, #ef944b, #e67519); /* Chrome 10+, Saf5.1+, iOS 5+ */
  background-image:    -moz-linear-gradient(top, #ef944b, #e67519); /* FF3.6 */
  background-image:     -ms-linear-gradient(top, #ef944b, #e67519); /* IE10 */
  background-image:      -o-linear-gradient(top, #ef944b, #e67519); /* Opera 11.10+ */
  background-image:         linear-gradient(to bottom, #ef944b, #e67519);
  color: #86420c;
  text-shadow: 0px 1px 0px #f6b17a;
  box-shadow: 0px 1px 1px #86420c;
  border-top: 1px solid #f1b07c;
}

button:hover {
  background-color: #e67519;
  background-image: -webkit-gradient(linear, left top, left bottom, from(#e67519), to(#ef944b)); /* Saf4+, Chrome */
  background-image: -webkit-linear-gradient(top, #e67519, #ef944b); /* Chrome 10+, Saf5.1+, iOS 5+ */
  background-image:    -moz-linear-gradient(top, #e67519, #ef944b); /* FF3.6 */
  background-image:     -ms-linear-gradient(top, #e67519, #ef944b); /* IE10 */
  background-image:      -o-linear-gradient(top, #e67519, #ef944b); /* Opera 11.10+ */
  background-image:         linear-gradient(to bottom, #e67519, #ef944b);
  color: #86420c;
}

button:active {
color: #733505;
background: #e67519;
position: relative;
top: 1px;
}

.noise {
    position: relative;
    z-index: 1;
    border-radius: 15px;
    }
.noise:before, .body-noise:before {
    content: "";
    position: absolute;
    z-index: -1;
    top:0;
    bottom:0;
    left:0;
    right:0;    
border-radius: 15px;
background-image: url(data:image/png;base64,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);
}    
    button > .noise {
        border-radius : 25px;
    }