Gellman at Sports Cards Uncensored has been front and center when it comes to exposing the dark side of our hobby... fake auto's and fake patch cards. His Scam Watch feature is a must read for the modern card collector.
Tonight, he looks at some football patch cards of questionable authenticity. There are links to many eBay auctions. I recommend heading over to his site and having a look.
That brings me to my question; how do fakers fake a card? How do they pry out a single color swatch, and replace it with some 5 color monstrosity?