Next September, British islands' postal administrations will certainly prosper on their old stamps for the 50th anniversary of the British regional issues.
In 1958, the Post Office issued the Wilding's royal effigy with symbols of the non-English parts of the United Kingdom (Northern Ireland, Scotland and Wales) and possessions of the Crown (Guernsey, Jersey and Man). Three for the first, three for the second ones.
In 1971, after the decimalization, the Machin series became regional too, but for the then postally independant Channel islands, and for the last time for Man. Here is an example of a Welch 26 pence:
The initial and redesigned symbols are the work of Jeffery Matthews, the other "father" of the Machin design since he rationalized its color scheme and inscriptions. The lack of currency ("p" for penny) was the choice of the Royal Mail in 1997 to avoid a Welsh Act imposing the use of the language in all regional context. However, penny is translated in ceiniog and neither the use of both "p" and "c", nor the possible confusion with a single "c", were considered acceptable.
Nowadays, the subjects of each four Kingdoms (including now England) can use a complete illustrated series of definitives and minisheet in the glory of their culture and symbols. Their values and designs are regularly renewed. These stamps are included in pre-personalized sheets (Smilers) figuring local landscapes and in prestige booklets (alongside a singing Royal Mail cash machine).
Stamp Magazine, in May 2008 issue, reports that a minisheet reproducing the first regional designs is previewed for this Autumn.
To go further:
* interview with Jeffery Matthews in the journal of the Great Britain Collectors Club, 2000.
* Douglas Myall, 40 Years of Machins - A Timeline, chronology published by the British Philatelic Bulletin, 2007. This $2.95 fascicule is available at the Royal Mail website.