This demo is using papervision3d technology to generate 3D t-shirt from bitmap in real-time and could upload the photo from user as well http://www.fishballstudio.com/dev/3dpv/ 
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This is DIY T-Shirt Demom which use flash and could upload photo from user directly: http://www.fishballstudio.com/demo/tshirt/tshirt.swf 
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