Milking Mice with Rainer
Rainer Brockerhoff is milking mice, it seems.
Oh, BTW: The way I always understood "Das ist ja zum Mäuse melken", it actually means something more like This could drive you to start milking mice. So, it doesn't indicate a tool that could be used for milking mice, but rather something that will drive you mad and do stupid things...
But then again, as a native speaker I never really bothered looking up what it means. Quite the opposite of some English phrases. For example, for a long time I thought it was "stock and trade" until I realized "stock in trade" made sense, too, and what do you know, the latter is actually correct. However, I'm still firmly convinced it's "should have" (contracted to "should've") not "should of", no matter how often people write that on TEH INT4RWEBZ.