Add me to the list! We used to see a lot of these little trains when we were about our business 'bird-watching' in the DDR. The fireman used to wave at us in a friendly manner, and the engineer was instantly on the radio reporting that he'd seen us.....happy days, eh? A very popular stretch for us was the Harzquerbahn/Wernigerode sub, and many a day was spent 'bird-watching' in that area, in spite of the continual interruptions from those noisy Russians and their smelly tanks and stuff.