Forensic anthropologists have created an image of what Bach really looked like based on his skull (which is in a museum somewhere). This was done by the same experts who reconstruct faces from skeletal remains for "missing persons" detectives. It looks quite a bit like the only portrait Bach ever actually sat for but totally unlike the cliched image we have of him.
http://www.bigpond.com/news/entertainment/...229/2176002.asp
The implication (since they use these artists' results to ID missing people) is that after looking at this portrait you would have been able to identify Bach on the street (!)