(Thanks to TV Cream for this cap)
Most of this post will be meaningless to anyone not from the UK, or under the age of 40. But then again...
Crackerjack was a children's entertainment television programme made by the BBC. It ran for nearly 30 years from 1955 until December 1984 and had a "variety" format where pop music and short comedy sketches were punctuated by competitions for members of the audience. As that audience was made entirely of schoolchildren, you can imagine how frenetic each show could be. It was rooted in England's music hall tradition and even in the 1950s must have seemed old-fashioned. (It certainly was when I watched it in the 1970s - see below.)
Inevitably, as with all competitions, there were winners and losers. Winners would be showered with games, toys and trinkets. Losers would receive a Crackerjack pencil, which was the idea of the show's producer, John Downes.
And it was only by losing at those games that you would obtain a Crackerjack pencil. Unlike the common Blue Peter badge, the supply of Crackerjack pencils was very tightly controlled. One (probably apocryphal) story has it that a BBC executive asked for one and was turned down flat, though the BBC did not turn the Queen down when she asked for some!
Since 1984, no new pencils have been given away. I've often wondered if there are any Crackerjack pencils left in the wild: perhaps as a stub languishing in a drawer somewhere, or someone's prize souvenir of their 60 seconds of fame. I've tried in vain to search for a picture of one, but Google Images gives me only pictures of a Cracker Jack Pencil Topper, which is not the same thing at all. Sometimes people put out plaintive requests on the internet for one. One of these things would command an astronomical price if it were to be put on the market - perhaps not as much as an original Thoreau pencil, but not far off. The Crackerjack Pencil is a culturally significant object to many adults here in the UK, an elusive butterfly, a reminder of lost youth.
(If you have one handy, let me know and I'll give you a fiver for it.)