JS1k: The JavaScript code golfing competition

C="▒▓███";n=35;a=[];M=['\n'];r=0;setInterval('a[r]=r=Math.random()*n|0;for(i=n*n;i-->n;M[i]=M[i-n]||C[a[i%n]--]||" ");document.body.innerHTML="<pre>"+M',n)

Qz0i4paS4paT4paI4paI4paIIjtuPTM1O2E9W107TT1bJ1xuJ107cj0wO3NldEludGVydmFsKCdhW3JdPXI9TWF0aC5yYW5kb20oKSpufDA7Zm9yKGk9bipuO2ktLT5uO01baV09TVtpLW5dfHxDW2FbaSVuXS0tXXx8IiAiKTtkb2N1bWVudC5ib2R5LmlubmVySFRNTD0iPHByZT4iK00nLG4p

//This is not really source a code, its just made longer and easier to read (I was not using this as a 'source' for compression)

C="▒▓███";
n=35;
seed=[];
M=['\n'];
r=0;

function render() {
  seed[r] = r = Math.random()*n|0;
  
  for (i = n*n; i > n; i--) {
    M[i] = M[i-n] || C[seed[i%n]--] || " ";
  }
    
  document.body.innerHTML="<pre>"+M
}

setInterval(render,n);