JS1k: The JavaScript code golfing competition

var c=document.getElementById('c'),w=window;w.onresize=function(){c.width=w.innerWidth;c.height=w.innerHeight;};w.onresize();var t=c.getContext('2d');var r=function(min,max){return Math.floor(Math.random()*(max-min+1))+min;};var p=function(c,t){this.c=c;this.t=t;this.s();};p.prototype={c:null,t:null,a:0,x:0,y:0,co:{},s:function(){this.a=.2;this.x=r(0,this.c.width);this.y=r(0,this.c.height/3);this.co={r:r(50,255),g:r(50,255),b:r(50,255)};},r:function(){this.a+=.05;this.y+=this.y*.01;this.x+=Math.cos(this.x*Math.PI)*4;this.t.fillStyle='rgba('+this.co.r+','+this.co.g+','+this.co.b+','+this.a+')';this.t.beginPath();this.t.arc(this.x,this.y,this.y/100+r(0,1),0,Math.PI*2,true);this.t.closePath();this.t.fill();if(this.y>=this.c.height||this.y<0||this.x<0||this.x>this.c.width)this.s();}};for(var i=0,pa=[];i<300;i++)pa.push(new p(c,t));setInterval(function(){t.globalAlpha=.1;t.fillStyle='#000';t.fillRect(0,0,c.width,c.height);for(var i=0;i<300;i++)pa[i].r();},20);

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