JS1k: The JavaScript code golfing competition

var d=Math,h=d.random,j=2*d.PI,k=500,l=k/2,n=l,q=0,r=l,s=n,t=[];d.a=d.cos;d.c=d.sin;a.d=a.beginPath;a.a=a.closePath;a.e=a.fill;c.width=k;c.height=k;c.style.cursor="none";for(i=0;50>i;i++)t.push(new u);function u(){this.x=k*h();this.y=k*h();this.b=j*h()}c.onmousemove=function(e){l=e.clientX-c.offsetLeft;n=e.clientY-c.offsetTop;e=l-r;var f=n-s;64<e*e+f*f&&(q=d.atan2(f,e),r=l,s=n)};
setInterval(function(){function e(b,e,f,g,m,p,v){a.fillStyle=p;a.d();a.arc(b,e,f,0,j);a.a();a.e();a.d();a.fillStyle="#EB2";a.arc(b+f*g,e+f*m,v,0,j);a.a();a.e()}function f(b,e,f){a.d();a.arc(b,b,e,f,f+6);a.lineTo(b,b);a.a();a.e();a.stroke()}for(i=0;50>i;i++){var b=t[i],g=n-b.y,m=l-b.x,p=d.atan2(g,m);b.b+=0<p-b.b-j*d.round((p-b.b)/j)?0.1:-0.1;b.b+=1*(h()-0.5);g=d.min(1,0.05*d.sqrt(m*m+g*g));b.a=d.a(b.b);b.c=d.c(b.b);b.x+=b.a*g;b.y+=b.c*g}a.fillStyle="#28E";a.fillRect(0,0,k,k);a.fillStyle="#8D3";a.strokeStyle=
"#372";f(400,50,0);f(345,40,1);for(i=0;50>i;i++)b=t[i],e(b.x,b.y,4,b.a,b.c,"#FE0",2);e(l,n,10,d.a(q),d.c(q),"#EEE",4)},20);

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