Hi folks,
I extended the Post-Box-Guesstimator[1] a bit:
http://toolserver.org/~ti/distance-o-meter/
It can be used for displaying and checking things "that should have a
certain density" like public phones or the famous dog-excrement-bag-
dispenser[2]. Radii can be adjusted according to your needs.
Regards,
Thomas
[1]
http://toolserver.org/~mazder/pboxguesstimator/
[2] Wer hat's erfunden? Die Schweizer natürlich!
http://de.wikipedia.org/wiki/Robidog