Today's post is a spiral, perhaps not as impressive as Jim Muth's FOTD 06-11-10
but incontestably a spiral. Ready made at http://maxitersfractalfollies.blogspot.com

 Yet Another Spiral  { ;     fract502.gif
                     ; blank
                     ; calctime   0:10:07.09
                     ; created Nov 06, 2010
                     ;  Fractint Version 2004 Patchlevel 10
  reset=2004 type=formula formulafile=kerrym.frm formulaname=km_04
  center-mag=0.167019/0.535127/24.2564
  params=-0.5/-0.5/-0.6354869228186896/-0.3533127842036195/-0.173558763389\
  996/-0.1402325510422071/0.08810693685720389/-0.7196569719534898
  initorbit=0.3/-0.6 float=y maxiter=1500 inside=0 decomp=256
  periodicity=0
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  }
frm:km_04{; Kerry Mitchell 26aug98
        ; tweaked by rjr so user can input julia parameters
        ; See the end of the formula general_man-2circ for
        ;    Kerry Mitchell's explanation of the "2 circles
        ;    coloring method".
        ;originally general_jul_test
        ; "2 general circles" coloring method for Julia sets
        ; c = Julia parameter, hardcoded originally to (0.65,0.33)
        ; p1 = x-circle center
        ; p2 = y-circle center
        ; real(p3) = x-circle radius
        ; imag(p3) = y-circle radius
        ; bailout hardcoded to 10^12
        ; use "decomp=256" coloring
        ;
  zc=pixel, c=p4, bailout=1e12, iter=1, rmin=1e12
  cenx=p1, radx=real(p3), rad2x=radx*radx
  ceny=p2, rady=imag(p3), rad2y=rady*rady:
  iter=iter+1, zc=sqr(zc)+c
  tempx=|zc-cenx|-rad2x
  tempy=|zc-ceny|-rad2y
  temp=tempx+flip(tempy), r=|temp|
  IF (r<rmin)
    rmin=r, z=temp
  ENDIF
  IF ((|zc|>bailout)||(iter==maxit))
    iter=-1
  ENDIF
  iter>0
  ;SOURCE: 98msg.frm
}
Roger Alexander