If you look at websites specializing in “ambigrams” you will find lots of devilishly ingenious typography work. Most ambigrams rely so much on old English letter forms or eccentric scripts, however, that they become sort of puzzle-like and perhaps not so well-suited for consumer product branding. The three above are exceptions.
These three ambigram/brand logos (in my grade-book) deserve high marks for legibility and typographic integrity.
Beach Packaging Design
(Note: see our earlier post about ambigrams here)