[Shan]

Certain weapons did have official names, such as Tiger and Panther, others such as PzIII and IV didn't - probably they didn't have any bicknames as well, at least I never found names for those tanks, for example.

Nicknames are called 'Landser-Ausdruck' (soldiers' slang: Landser= something like a grunt= ordinary foot soldier in the egrman army): Certain infamous, badly-working or dangerous weapons, but also generals, standard army procedures, etc, received appropriate nicknames from the common soldiers - the best example I can think of would be the the 3,7cm Pak being called 'Panceranklopfgeraet' (tank-knocking device... free translation ;-)) as it proved to be ineffective against medium-armored tanks. Another one: 'Rommel-Spargel' (Rommel's asparagus) for the wooden poles erected by the thousands throughout the west to deny open spaces to glider landings; the Wehrmacht used captured russian 7.62cm universal field gun/AT gun in considerable numbers, called 'Ratsch-Bumm' by the soldiers (something like Whamm!-Bang! ;-)), and the Katyushas were, as you might know anyway, called Stalinorgel; the russian submachine guns such as the PPsH-41 were called Molotov-Guitar; a shot wound serious enough to guarantee you a ticket back home is called 'Heimatschuss' etc...

There are many more... I even got a WW2 encyclopedia where a lot of this soldiers' slang is mentioned, if you want more on that!