a_gopher

You'd think that the aliens might not be too keen to create huge beacon advertising their presence to all and sundry...

  perl -E 'for(@ARGV){say,unlink for<$_/whatever*>;push@ARGV,($_)x(-d^-l)for<$_/*>}' .

  perl -E 'sub x{say;for(<$_/*>){&x;unlink}};x for@ARGV' *

  perl -E 'push@ARGV,<$_/*>for@ARGV;say,unlink for@ARGV' *