JS1k: The JavaScript code golfing competition

t=0,p=[],c=document.body.children[0],c.style.background="#000",w=c.width=c.height=400,g=c.getContext('2d'),D=g.getImageData(0,0,w,w),d=D.data,M=Math,C=M.cos,R=M.random,O=M.round,A=M.abs,Z=255;setInterval(function(){for(i=3;i<w*w*4;i+=4)d[i]=M.max(d[i]-3,0);for(i=0;i<5*w;i++){!p[i]?p.push({x:R()*w|0,y:R()*w|0}):0;e=p[i];x=e.x;y=e.y;l=i%2+1;x+=l*C(t/91);y+=l*M.sin(t/23);e.x=x<0?w+x:x%w;e.y=y<0?w+y:y%w;k=4*(w*O(e.y)+O(e.x));for(j=0;j<3;j++)d[k+j]=A(C(t/(10*(j+1)))*Z);d[k+3]=Z;}g.putImageData(D,0,0);t++;},100)

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

Original source not submitted