If you have never heard of Yu-Gi-Oh, and haven't realized that it is taking over the world, you are not alone.
Practically unnoticed by adults, this Japanese-devised trading card game has been spreading round the world, sucking pocket money out of boys' pockets faster than the monster characters in the Yu-Gi-Oh storyline can strike a blow.
In German schoolyards in recent weeks, Yu-Gi-Oh trading cards have been an instant key to popularity. A boy fanning out his collection in a park can count on a dozen other kids showing up to rubber-neck at what he has got within a matter of seconds.
The cards show cartoon-style monsters and the game plan is based on the story of Yugi, a young boy who possesses a "Millennium Puzzle" that allows him to transform into a "Game King" when challenged. Players have to memorize game lore and complex points tables.
The German-language version of the cards went on sale in April, and leisure industry sources say the local licensee, Amigo, sold out the first two print runs despite startlingly high prices for the cards and is well into the third.
Children pay 7 euros (US$8) or more for an envelope containing nine of the trading cards, more than two weeks of the average boy's pocket money according to a recent survey of 6-to-14-year-olds by the TV channel Fox Kids.
The 3.43 euros a week registered by Fox rises to 10 euros a week for 13-to-17-year-olds, according to a separate survey by Cologne economic research institute IW in January, so the cards are more affordable for teens, who also know how to buy them second-hand on Internet auction sites like eBay.
Trade sources say retailers can choose whatever markup they like for the cards, and that Amigo wholesales them at the same price as its other big seller, Pokemon cards, which arrived in Germany in 1999.
Children interviewed in Hamburg say Pokemon cards currently retail at about half the price of a Yu-Gi-Oh pack. The industry has no compunction about squeezing the maximum price out of children: you can't learn soon enough that it's a cold, hard world out there.
Last week the European Commission opened distortion-of-competition proceedings against Topps, the company next up the rights chain, accusing it of ensuring Finnish children paid two and a half times as much for Pokemon cards in 2000 as Portuguese children did.
Competition Commissioner Mario Monti said Topps had enforced "a complete ban on exports" from low to high-price countries. Topps has assured the EU it now complies with competition rules.
The European market for stickers, cards and other collectible products bought by children was worth more than 600 million euros in the EU and Switzerland in 2000, according to EU estimates. With the profits so high, parallel imports of Yu-Gi-Oh cards into Germany are in full swing. Many children trade English-language versions of the cards, which are on sale in shops for slightly less. The game went on sale in Britain last year.
Huge numbers of forged cards are also in circulation.
Konami, the Japanese company behind the cards, has devised security features for Yu-Gi-Oh that come close to those used on banknotes:
holograms, fine print, difficult-to-copy colors.
It is not clear where the forgeries are coming from, but they are easily spotted by the practised eye: the hologram is often just a speck of blank aluminum foil, the cardboard is too thick or too thin, and the colors on the standard reverse of the card look wrong.