button.html

<button id="btn-0">Button 1!</button>
<button id="btn-1">Button 2!</button>
<button id="btn-2">Button 3!</button>
<script type="text/javascript">
    var prizes = ['A Unicorn!', 'A Hug!', 'Fresh Laundry!'];
    var btnNum = 0;
    for (var x = 0; x < prizes.length; x++) {
        // for each of our buttons, when the user clicks it...
        document.getElementById('btn-' + btnNum).onclick = function() {
            // tell her what she's won!
            alert(prizes[btnNum]);
        };
        btnNum = btnNum + 1;
    }
</script>