One of our readers brought our attention to the photo on the right, taken by Otzonski on Flickr. The photo on the left is taken near here, in Copenhagen - traffic lights for bikes at an intersection.
It is cool to see the same lights in action in Berlin - on Karl-Marx Allée - with a wonderful personalised touch that you really only find in the fantastic Mitte area of the city.
Here's the Copenhagen version of the lights in action:
What you see is a classic Copenhagen bike lane. In this instance there is a lane for riding straight on as well as a turning lane for bikes crossing to the left. It's not a normal intersection, just a crosswalk for people heading to the metro station and for bikes crossing to get to the Copenhagen Business School and the bike path down the hill.
The traffic lights are visible. On the right of the photo there are the two lights for the different directions - straight on or turn left. And, on the median, there is another light for the left turners.