It's been done, Scott. Check out GCGA7A
or, more specifically, my log of
[URL=
http://www.geocaching.com/seek/log.aspx?LUID=0b4ccb77-b494-432f-aed9-2c42520abd7a]02/28/04[/URL].
Of course, this cache has been archived but it was around for almost a year and
quite literally right under the nose of the authorities. I agree with you
though on the over-abundance of "stealthy" urban micros. Many times I have
passed over caches because I felt they were too "risky", at least at the
time.
-- Sprocket
P.S. I know the above cache is OOS, so that's
probably why you've never seen it before.
;-)