Describe OctoThorp here.

''okay. It looks like this -->'' #

Ask your nearest Brit if that is a "pound sign"...

''It isn't.''

        #    #
     #####
      #    #
     #    #
  #####
   #    #

Count the thorps. There are 8. Hence - octothorp
----

PhlIp twice edited the over-sized OctoThorp above, making it symetric, like it was when he first wrote it. If he is not, indeed, opposing a wiki vandal, is he opposing someone with a curious font setting?

''Most curious.  The over-sized OctoThorp is now entirely not an OctoThorp, post re-edit by PhlIp.  My font settings are, to my knowledge, precisely the defaults supplied in FireFox 3.0 (Windows XP and Linux) and InternetExplorer 7.0 (Windows XP).  My edit to said OctoThorp (and the reversion of Ph1Ip's edits) was an attempt to make it symetric, which it was not.  I've left it in its (non-symetric to me, symetric to PhlIp) state, pending resolution of this peculiar puzzler.''

k now the arms are way too short. 5 hashlets in each of the two cross-beams is no longer working. Maybe my Firefox caught the issue you have. Now I see this as correct:

        #    #
     ##########
      #    #
     #    #
  ##########
   #    #

AsciiArt is an exact science, in a monospaced font, right? May the second one will get long for me, presently...

{Symmetric counts would work for a vertical number sign:}

    # #          #  #
   #####        ######
    # #    or    #  #
   #####         #  #
    # #         ######
                 #  #

{But once you tilt it, the horizontal bars need to cross the additional horizontal distance spanned by the vertical bars. The horizontal tilt is +5 spaces for the vertical bars (one per unit height), so the horizontal bars may be 10 or 11 units width. Yours is a the correct one with a tilt.}