JS1k: The JavaScript code golfing competition

m="left|width|height|top|background|color|position".split('|');A=120;q=Math.random;d=(r=document)[N='createElement']('textarea');k=r[N]('a');k[D='style'][m[6]]=U='absolute';n={6:U,0:0,3:0,1:z='300px',2:z,4:T='transparent',5:T};for(x in n)c[D][m[x]]=d[D][m[x]]=n[x];k[D][m[0]]=(c[m[1]]=c[m[2]]=v=parseInt(z))+14+'px';b[C='appendChild'](d);b[C](k);e=c.getContext('2d');s=[];L='length';d.onkeyup=f=function(k){c[m[1]]=v;e.font=d[D].font='14px arial';n=d.value.split('\n');l=0;for(x in n)e.fillText(n[x],3,l+=F=14);l=e.getImageData(0,0,v,v),o=l.data;for(i=0;O=s[i],i<s[L];i++){o[O[0]]==0&&(s[i]=[0]);for(j=0;j<O[L];j+=2){r=q();o[O[j]-2]=O[j+1]+F*r+A;o[O[j]]=2*A;if(O[L]>F)continue;r<.05&&s[i].push(O[j]+A*10,A*r)||r<.1&&s[i].push(O[j]+4,A*r)}}for(i=0;!k&&i<o[L];i+=4)if(o[i+3]!=0&&q()<1/s[L])s.push([i+3,A]);s=s.filter(function(n){return n[L]>1});e.putImageData(l,0,0)};g="lufituaeB = erutaN = modnaR".split('');setInterval("n=g.length&&(d.value+=g.pop());f(f(n))",v);k.innerText="Add your own Text and let the Moss take over"

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

d=document.createElement('textarea');
k=document.createElement('a');
n = {'position':'absolute','left':0,'top':0,'width':z='300px','height':z,'background':'transparent','color':'transparent'}
for(x in n){
  c.style[x]=d.style[x]=n[x];
}
k.style['position']='absolute';
k.style['left']=(c.width=c.height=v=300)+14+'px';
b.appendChild(d);
e = c.getContext('2d');
s=[]

d.onkeyup=f=function(k) {
  c.width=v; //Redraw canvas.
  e.font=d.style.font='12px arial';
  n = d.value.split('\n')
  l=0
  for(x in n) {
    e.fillText(n[x],3,l+=14)
  }
  l=e.getImageData(0,0,v,v),o=l.data;
  for(i=0;i<s.length;i++) {
    o[s[i][0]]==0 && (s[i]=[0]);
    for(j=0;j<s[i].length;j+=2) {
      r=Math.random();
      o[s[i][j]-2] = s[i][j+1]+120+14*r;
      o[s[i][j]] = 255;
      if(s[i].length>20)
        continue;
      r<.05&&s[i].push(s[i][j]+1200,120*r) || r<.1&& s[i].push(s[i][j]+4,120*r)
    }
  }
  for(i=0;!k&&i<o.length;i+=4) {
    if(o[i+3]!=0&&Math.random()<1/s.length) {
      s.push([i+3,120]);
    }
  }
  s=s.filter(function(n) {return n.length>1;});
  e.putImageData(l,0,0);
}
// Initial Text
g="lufituaeB=erutaN=modnaR".split('')
setInterval("n=g.length&&(d.value+=g.pop());f(n),f()",v);
// Help
k.innerText="Add your own Text, and let the Moss take over."
b.appendChild(k);