Another entry (EPILEPTIC PEOPLE: do not try! You're warned :) )
(253 bytes).
a#=257;Graphics a,a;a:/2;SetOrigin a,a;While 1;j#=Sin(t*3);k#=Cos(t*7);l#=Sin(t*5);For x=-a To a;For y=-a To a;u#=x/a;v#=y/a;i#=Sin((ATan2(u,v)+Sin((u*u+v*v)^l)*a*a*k)*Int(j*50))+1;SetColor i*(j+1)*a,i*(k+1)*a,i*(l+1)*a;Plot x,y;Next;Next;t:+1;Flip;Wend
(253 bytes).