I have a couple; my favourite is a coin that was not intentionally a "Christmas coin", but which became one owing to its nature and design.
The British crown of 1927-1936 was an NCLT coin, re-introduced just for sale to collectors after the denomination was withdrawn from general circulation. Lobbying from the British Numismatic Society was primarily responsible for the issue. More formally known as the "wreath crown" for obvious reasons, they were common Christmas gifts to collectors back when they were issued (just as RAM sets are common gifts today, I would imagine). Hence they are also known as "Christmas crowns".
