Don Fluckinger, who monitors online auction results for a weekly column in SPORTS COLLECTORS DIGEST, notes that a Brett Favre rookie card carrying a PSA 10 grade sold for $6,600 in an eBay auction last week.

The price alone is not the only amazing tidbit about this story. The card that commanded this price was a 1991 Wild Card "1,000" card of Favre.

Anyone who was collecting football cards in 1991 might remember Wild Card's unique marketing concept for trading cards. Similar to many of today's products, Wild Card offered parallel cards in various degrees of scarcity. But Wild Card offered a twist to this concept. Each level of parallel cards carried a denomination. Base cards were considered a "1," the next scarcest level was labeled with a stripe that read "5," the next scarcest featured a "10," "25" and so on. A card with a "1,000" stripe was the scarcest you could find.

The reason for the numbering was that Wild Card offered collectors a chance to trade up their cards to get a more scarce version. For instance, if you collected 25 Favre base cards, you could send them to the company and trade them in for a single "25" card. Get four "25" cards and you could trade for a "100" card.

The concept didn't really catch on and Wild Card eventually went bankrupt after a controversy surrounding a football prospects set that ended up being printed in much higher numbers than the company advertised. Most of the company's products attract very little attention on the secondary market these days, which is why the $6,600 selling price was so stunning. Perhaps the excitement surrounding Favre's great 2007 season got the better of one collector.