Planet Perplex Wordplay - Gallery of ambigrams, drawings with words and other wordplay. - http://www.planetperplex.com/en/ambigrams.html
01101001 Ambigrams - A gallery of ambigrams by 01101001, a computer fan. - http://www.01101001.com/ambigrams/
World Play - Ambigrams by Cihan Altay in Turkish, translated into English. - http://otuzoyun.com/wordplay/
Ambigrams by Brett J. Gilbert - Small gallery of typographic designs based on people's names. Includes a variety of different ambigram types and some explanatory text describing the challenges and successes of each design. - http://www.55cards.com/paragraphic/ambigrams/
John Langdon - Presentation of his artistic-like ambigrams. - http://www.johnlangdon.net/
Uahlim's Ambipur Gallery - Ambigram gallery with a matrioska ambigram. Mostly in Italian but still appreciable by all. - http://www.revil.it/ambipur/
Ambigrams - Contains a few ambigrams including 2 four-word ones and a circular one. - http://thinkzone.wlonk.com/Ambigram/Ambigram.htm
Gef's Ambigram Gallery - French site in English, involving ambigrams of French people and phrases. - http://www.iap.fr/users/esposito/ambigallery.html
Upsidedown Truths - Ambigrams involving Christian concepts. - http://www.crazytieguy.com/upsidedown.htm
Spanish Ambigrams - Although in Spanish, the viewer can appreciate the ambigrams by clicking on the figures. - http://ambigramas.com
Ambigram.Com - Contains Ambigram-Matic for creating your own personal ambigrams online, plus reversible matchbox art and links. - http://ambigram.com
Scott Kim's page - Contains examples of Scott Kim's ambigrams. - http://www.scottkim.com/
Ambigrams by Stefan Gustavson - Introduction to ambigrams, information about how the writer got involved in them, recommended book, and some of the author's own ambigrams. - http://www.itn.liu.se/~stegu/ambigrams/