I had to laugh when I heard about researchers at New York's Clarkson University had discovered you can fool fingerprint scanners with a Playdoh image of someone's finger.
I remember chatting to Identix, one of the first biometric scanner companies about how easy/difficult it was to fool their scanners in the mid-to-late 1990s.
The discussion I had with Identix, at the CeBIT Computer Faire in Hannover, Germany, was quite open. They said that if anyone chopped (yes, chopped!) off a finger, it would only read into a scanner for a few minutes, as the loss of blood pressure would cause the fingerprint image to fade.
With clay or similar impressions, the problem was that the general graininess of the clay does not give enough resolution to create a fine enough resolution replica of the real fingerprint to fool the scanner.
Playdoh, on the other hand, is very smooth stuff - and wears out quite quickly, as any parent will tell you - so it should be capable of replicating a fingerprint.
As the researchers at Clarkson have confirmed. In their tests, they created 60 fake fingerprint images and managed to fool a fingerprint scanner system and its software in 90 per cent of cases.
Gelatine can also be used, but that's rather messy, although even Playdoh isn't the kind of stuff you can fool the owner of a fingerprint into giving.
Holographic imaging - now that's another story...