Interesting. I’ve never heard that before, but I have heard them called Einkaufspanzer (shopping tanks) several times. The implication being it’s the tank you use to do your grocery shopping in.
I run Sales for Founders (https://salesforfounders.com) - a course where I teach (mainly technical) founders just enough about sales to find their first customers and grow to $10k MRR.
Since starting work on the course in May, I’ve been through 3 iterations and made about $40k.
The ‘final’ version of the course will open for sale in early November, and I expect it to continue to be my main source of income for the next year or so at least.
If you’re thinking about running a course (I was very sceptical at first) or want to hear more, you can check out my recent interview on the IndieHackers.com podcast.