JS1k: The JavaScript code golfing competition

m=window;g=255;d=document;n=Math.random;c=Math.abs;e=d.body.children[0];h=w=143;e.width=m.innerWidth;e.height=m.innerHeight;sw=e.width/w;sh=e.height/h;var f=e.getContext("2d");f.c=f.fillRect;function j(a,b,k){f.fillStyle="rgb("+a+","+b+","+k+")"}function l(a,b){if(a.x<a.a)a.x+=b;if(a.x>a.a)a.x-=b;if(a.y<a.b)a.y+=b;if(a.y>a.b)a.y-=b}function o(a,b,k){if(c(a.x-b.x)<k&&c(a.y-b.y)<k)return 1;return 0}function q(a,b){a!=b.d&&o(a,b,2)&&r();if(p!=a&&o(a,b,4))a.x+=1}function t(){this.x=w/2;this.b=this.a=this.y=0}var u,v;function r(){u=[];p=new t;v=new t;v.y=h}r();function x(a){f.c(a.x*sw,a.y*sh,sw+11,sh+11)}e.onmousemove=function(a){p.a=a.clientX/sw;p.b=a.clientY/sh};function y(a,b,k){s=new t;s.x=a.x;s.y=a.y;s.a=b;s.b=k;s.d=a;u.push(s)}e.onmouseup=function(a){y(p,a.clientX/sw,a.clientY/sh)};setInterval(function(){j(10,0,0);f.c(0,0,w*sw,h*sh);j(0,g,0);x(p);j(g,g,0);x(v);j(g,0,0);for(i=0;i<u.length;i++){s=u[i];f.c(s.x*sw,s.y*sh,sw,sh);l(s,1);q(p,s);q(v,s)}v.a=p.x;v.b=p.y;n()>0.96&&y(v,p.x,p.y);l(p,0.7);l(v,0.4)},40);

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

Original source not submitted