Prezi Compo entry - 662 bytes

index.html

<style>body{overflow:hidden}z{display:none}w{position:absolute;top:50%;margin:0 auto;width:100%;text-align:center}</style><z><x>hello world</x><x>simple presentation tool</x><x>one feature:</x><x>zoom</x><x>by TBD/plugins.ro</x></z><w id='s'></u><script>b=1;c=0;d=8;e=document.getElementsByTagName("x");l="fffeeebbbaaa888444222000";function r(){if(b>d)c+=1,b=1;else if(b<0)c-=1,b=d;if(b<d)s.innerHTML=e[c].innerHTML;x=s.style;x.MozTransform=x['-webkit-transform']="scale("+b+")";x['color']='#'+l.substr(3*b,3)}t=function(e){m=e.wheelDeltaY||-e.detail;g=m&&m/Math.abs(m);b+=0.3*g;r()};q=window.addEventListener;q('mousewheel',t,0);q('DOMMouseScroll',t,0)</script>