German Stamp Collection

I bought a few hundred stamps for a couple of dollars, and these were with them (I picked this lot specifically due to high number of German stamps.)

Many of you know how I like Germany, as it was my ancestors' home, so here ya' go.

Interesting ones are 10 million mark, which would be like a 10 million dollar stamp, and stamps that one day were, say, only 400 mark and the next became 100 thousand mark.
Those were Weimar Republic era, AKA the inflationary era, about 1923.
(The stamp in my hand at upper right is Austrian. I got it mixed in with these accidentally when ordering by country.)