3-d push button effect, no JavaScript nor images, pure CSS - http://www.webcredible.co.uk/user-friendly-resources/css/more-css-tricks.shtml
<p class="buttonlike"><a href="#" title="buttonlike link">buttonlike link</a></p>
.buttonlike a {
background:#fc0;
border:1px solid;
border-color:#aaa #000 #000 #aaa;
display:block;
text-align:center;
text-decoration:none;
width:111px;
}
.buttonlike a:hover{
border-color:#000 #aaa #aaa #000;
left:1px;
position:relative;
top:1px;
}
<a class="like-a-button" href="#">This</a> <a class="like-a-button toggle" href="#">That</a>
.like-a-button{
background:url(like-a-button.jpg) left center no-repeat;
display:block;
font-size:11px;
height:15px;
line-height:14px;
margin:3px 0;
padding-left:33px;
padding-top:2px;
width:93px;
}
.like-a-button.toggle{
background:url(like-a-button-toggle.jpg) left center no-repeat;
}
.like-a-button:link,
.like-a-button:visited,
.like-a-button:hover,
.like-a-button:active{
color:#aaa;
text-decoration:none;
}