While tuning across the HF bands tonight I stumbled upon this strange signal on 40m, firing up Multipsk I took a hunch that it was some form of teletype transmission and discovered it was in fact Hellschreiber.
You can read all about it on Wikipedia http://en.wikipedia.org/wiki/Hellschreiber
The original mechanical Hellschreiber facilimile machine was first developed in the late 1920s, and saw use starting in the 1930s, chiefly being used for land-line press services. During WW2 it was sometimes used by the German military in conjunction with the Enigma encryption system. In the post-war era, it became increasingly common among newswire services, and was used in this role well into the 1980s. Today Hellschreiber is used as a communication mode by amateur radio operators using computers and sound cards; the resulting mode is referred to as Hellschreiber, Feld-Hell, or simply Hell.
Sorry about the poor quality of the video, hopefully you can make out some of the text in this QSO.