Smallest Mandelbrot program

This mandelbrot program is even shorter than 8 lines. With its 4 lines it prints a small mandelbrot in ascii characters. It is part of OpenBIOS (http://www.openbios.org):

hex 4666 dup negate do i 4000 dup 2* negate do 2a 0 dup 2dup 1e 0 do
2swap * d >>a 4 pick + -rot - j + dup dup * e >>a rot dup dup * e >>a
rot swap 2dup + 10000 > if 3drop 2drop 20 0 dup 2dup leave then loop
2drop 2drop type 268 +loop cr drop 5de +loop