Auto Scroller for reading in websites

(Chrome:) Ctrl+Shift+J
Paste:

var x = 0;
var s = 0.23;
window.setInterval(function(){
    if(x<=document.body.clientHeight){
        x+=s;
        document.body.scrollTop = x;
    }
},100);

Have fun reading (s= [0.2 - slow, 0.35 - normal, 0.5 fast])!

----UPDATE----<br />
I've updated the code to be more "user friendly",<br />
Create a book mark and add the following in the URL input field:<br />

javascript:var x =prompt("Start From:",window.pageYOffset );x=1x;var s    =prompt("Speed:",0.03);s=s1; window.setInterval(function(){ if(x<=document.body.clientHeight){ x+=s; document.body.scrollTop = x; } },10);
</code></pre>