A useful new control would be : RadWebcam

It would show webcam view in realtime and call a function each x seconds (or ms), would be useful for :
 - user picture to attach to its user account
 - quick product picture
 - and for my need : call an external function for barcode recognization

I think it would be easy and fast to create this control for WPF, and it would fit perfectly with Silverlight 4 (or 5 ?) webcam support.