Stamp errors in general and inversions in particular have been a fascination for collectors since the hobby began and continues to be so today.
The Western Australia 1854-55 4d blue inversion error (inaccurately described as the 'Inverted Swan', when actually it is the frame around Swan which is inverted) was one of Thomas Tapling's prized possessions whilst the spectacular Mahendra Sagar collection has just been sold at Siegel.
The Indian stamp world record price is currently held by an 1854 inverted Queen Victoria from India, whilst of course a block of the world famous Inverted Jenny stamps which so impressed Col E H R Green currently represents the world's most expensive philatelic item at $2.97m (thanks to Bill Gross).
But to experienced philatelists, these are perhaps a little over-familiar. So here are five of our other favourites from around the world:
A town turned upside-down: Dendermonde
Belgium's greatest contribution to error stamps much surely be the Inverted Dendermonde (or Termonde in French). Showing one of the town's buildings upside down, it is thought to be worth around $100,000.
There are just 14 copies known to exist, one of which is in the collection of chess legend Anatoly Karpov.
You've been framed: Jamaican 1 shilling
One of the most attractive stamp designs around was created in Jamaica. Strangely unaffecting its look and presenting one of the nicest frame inversions in existence, the 1920 issue tends to be sold for five figure sums in good condition.
Mirror-writing: Orange 1 kopeks
Inverted Jennies weren't the only topsy-turvy stamps that Bond King Bill Gross specialised in. There was also a fine Russian 'pair' with the inscription reversed.
Two singles which are previously thought to have been a pair were re-joined and offered at Cherrystone's December 2010 auction.
These 1k orange invert stamps were once part of the Mikulski and Fabergé (of ornamental eggs fame) collections, and would make a spectacular centrepiece, being catalogued at $75,000.
Can't hold a candle to you: CIA inverts
The Inverted Jenny is not an especially rare stamp, with 90-odd examples still known to exist. Why it is so valuable is a question frequently asked by philatelists who compare it to the famous (but less so) CIA inverts.
The modern error results from the 1979 inverted $1 Rush Lamp design which was intended to show a particularly brilliant candle beaming its orange light out of an otherwise black and beige stamp to illustrate America's hope, truth and reason.
In fact, the separate colour printing left the main candle looking drab with the whole stand at risk of being ignited by a mysterious golden exclamation mark.
The issue has a similar number of known examples in existence (in the nineties), but tend to be worth low five-figure sums rather than high six-figure ones like the Inverted Jenny.
It gained its moniker as the error was discovered by a CIA employee who went out to buy stamps for the agency. The CIA tried to claim that the stamps were theirs as he was buying stamps for work use, but to no avail.
Backhanded payments: the Red Revenue surcharge
Finally, an impressive invert error on one of China's most popular Imperial stamps helped to bring Interasia a world record for their auction in the spring of this year.
The corner strip of three from the 1897 Red Revenue series the $5 surcharge inverted fascinated bidders and finished easily top of the section. It is one of the most spectacular Chinese philatelic lots we have ever seen.
Collectors interested in fine inverted surcharge errors should take a look at this fascinating Newfoundland stamp.