Michael:
GeoNet has downloadables for all countries but the USA. That defect is
filled by the USGS, which provides state-by-state data for the US and
some outlying territories and ex-territories (giving a little overlap
with GeoNet in places). The USGS also provides a fascinating Antarctica
gazetteer text file, giving the naming circumstances and toponymy for
close to 17000 Antarctic features. And GeoNet provides databases for
undersea features and oceans, too.
A while back, through the miracle of a cable modem, I ripped all this
stuff down off the relevant websites and whiled away some happy hours
running it all through various macros to convert GeoNet's unique
character coding system to Unicode, and to lay the stuff out the way I
wanted it. So I'm now the proud owner of three CDROMs containing XLS
files with feature names (+ lats longs etc) for every country in the world.
Antarctica was a problem, database-wise, since it's hard to automate the
separation of the names, lats and longs from all the gazetteer info. But
spurred on by interest, a heavily hand-assisted run-through tonight has
met with success.
So my (almost certain) extreme south-latitude palindromes are:

Mom peak 85 27 S
Massam glacier 84 33 S
Hannah ridge 83 36 S
Mount Ege 83 34 S
Hannah peak 82 36 S

The gazetteer story on Mom Peak is sufficiently pleasing that I'll quote
it: "A peak (3,260 m) in eastern Otway Massif, 5 mi SE of Mount Petlock.
Mapped by USGS from surveys and U.S. Navy air photos (1959-63). This
name recognizes the activities of Shirley (Mrs. James C.) Anderson of
San Diego, CA, widely known as "Antarctica Mom" among U.S. personnel
wintering over in Antarctica. In the years following 1961, Mrs.
Anderson communicated with thousands of wintering personnel in
Antarctica and her efforts contributed greatly to their morale."

Re the palindrome-detector:
It's an Excel macro which (at present) runs through any highlighted area
cell by cell, supressing spaces and punctuation and looking for single
palindromic words, or complete palindromic strings. When it finds a
palindrome it highlights it in red.
So it'll pick up "Hannah Peak" and "A man, a plan, a canal: Panama!",
but it won't spot palindromes as substrings, like (imaginary) "Eka Lake
Point". And it *will* latch on to partials like "Bob Bartlett Glacier"
(86 15 S).
You're of course welcome to a copy, though it needs some primping before
I'll let it out: it needs at least a little start-up form to allow
option selection, a report form to say what's been found, and the
facility to dump all retrieved palindromes on to a separate sheet for
easy browsing.

Re The Extreme Palindrome Quest, GeoNet gives names with and without
diacritics, which adds a new complication or delight, depending on your
viewpoint. (BTW I'm pleased that the old Greenlandic spelling of Qaanaaq
is still palindromic - Qânâq. Same long vowel, different spelling.)

Grant