From AndyRG at VirtualTourist.com:
Be careful!Woohoo! Let the games begin!
We seem to have a confuse about the green and the red colour... When you see the green traffic light for the pedestrians, that doesn't mean that you can walk immediately to the other side! What a claim you have! The drivers almost never respect the right of way, which belongs to the pedestrians. So, look very carefully at any direction before your next step...
Demonstrations
There are innumerable demonstrations all the time at the centre of Athens, against... everything (many strikes through the year too). Even a few persons who protest are able to make the traffic tangle more chaotic (if it isn't already the worst it can be...)
Sexually transmitted disease
After the collapse of communism in eastern european countries (since 1990 and so on), many women from these countries were forced to be prostitutes in Athens too...
Their exact number is difficult to be counted, but it is considered to be enough thousands of them. Almost none of these women has a lisence for this job and you can't be sure about the right conditions of hygiene...