CSS3 provides some nifty animation capabilities. Below is an example of using the CSS3 transform property, combined with the :hover pseudo class, that provides some nice interactive effects. Hover your mouse over each picture to see it work
.zoom {
float: left;
transition: transform;
transition-duration: .5s;
max-width: 200px;
margin-right: 5px;
margin-bottom: 5px;
z-index: 0;
}
.zoom:hover {
z-index: 1;
transform: scale(1.5);
box-shadow: 0px 0px 15px rgba(200,0,0,.5);
}