JS1k: The JavaScript code golfing competition

ti=0;sp=[];sb=[];sc=0;c.width=c.height=500;function oc(e){sb.push({x:e.pageX,y:e.pageY,r:10});}
document.onclick=oc;df();function df(){if(ti%10==0){var xpos=Math.floor(Math.random()*501);sp.push({x:xpos,y:200,z:0.01});}
ct=a;ct.clearRect(0,0,500,500);ci(250,2400,2205,'lightgray');for(var i=0;i<sp.length;i++){var x=sp[i].x,y=sp[i].y,z=sp[i].z;ci(x,y-(90*z),20*z,'green');ci(x,y-(50*z),30*z,'green');ci(x,y,40*z,'green');sp[i].z+=0.01;}
for(var j=0;j<sb.length;j++){var s=sb[j];if(s.r>2){ci(s.x,s.y,s.r,'grey');s.r-=1;}
else{findColl(s);sb.splice(j,1)}}
ds();setTimeout(df,100);ti+=1;}
function ci(x,y,r,c){ct.fillStyle=c;ct.beginPath();ct.arc(x,y,r,0,Math.PI*2,true);ct.closePath();ct.fill();}
function coll(m,t){var a=Math.abs(m.x-t.x);var b=Math.abs(m.y-t.y);var d=Math.sqrt(a*a+b*b)
if(d<20){sc+=100;return true;}
return false;}
function findColl(m){for(var i=0;i<sp.length;i++){if(coll(m,sp[i])){sp.splice(i,1);}}}
function ds(){ct.fillText("score: "+sc,10,10);}

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

Original source not submitted