Alain is right, but if you care to be indecent (about your download times and picture quality that is), there is the CMUCAM. It can send the picture (and a very low resolution one at that) through the serial port. It's value lies more in the way it can process the images, and figure out where red dots are, etc. Their original CMUCAM could do something similar, but as I remember, reaction times were much slower than this video for the CMUCAM3 http://www.cmucam.org/
And for a $50.00 camera that just outputs serial, with no image processing: http://www.sparkfun.com/products/10061
As Alain says, "decent" is the key term here. These are LOW resolution pics here.
Edit: This picture if from the sparkfun camera. Not so bad, I guess:
Here is some info on wireless CMUCAM: https://sites.google.com/a/asu.edu/w...nsmission-demo
And last bot not least (I think Ken might like the line following bots at the end) Here is a video for the original CMUcam.
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