I scoured EQ Zone Viewer a few years ago, trying to find secret areas.
EDIT: Now that I think about it there are quite a few areas that come to mind. The secret Room below Tazgar's Room in the Temple of Solusek Ro, etc. I know there was a weird secret room in PoM, but what it was and how it happened escapes me.
There were also several rooms that GM's would banish players to, for instance Befallen's cat room:
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Check out EQ Zone Viewer, you'll find lots of stuff.
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