Cartridge code (253 chars):

function r(x,y,d,a,b,c)local e,f=x+cos(a)*d,y+sin(a)*d
for j=-b,b,b do
if(c>6)line(x*⧗,y,e*⧗,f,10)break
r(e,f,d/2,a+j,b,c+1)end
end
camera(-64,0)::★::
for i=24576,32767 do
poke(i,peek(i)/4)
end
⧗=cos(t()/4)
s=96+sin(t()/8)*64
r(0,64+s,s,.25,1/3,0)goto ★