Some-when in the 00's I read an article about him that he was putting advanced networking stuff into the castle and had the intention to start something like a "think-tank" (doesn't really fit it, but I don't know what I'd call it) where he and others would hang around and code stuff.
I found the article [1] from July 2002, "Lord of the Castle Kai Krause presents Byteburg II".
> So that 's Kai Krause's long-cherished plan: Now the software guru has finally opened a center for founders and developers from the IT and software industry in Hemmersbach Castle near Cologne -- the Byteburg II
I really wonder what he's doing to these days. His plug-ins were legendary, as well as the User Interface for Bryce [2]
[0] https://de.wikipedia.org/wiki/Burg_Rheineck
[1] https://www.heise.de/newsticker/meldung/Schlossherr-Kai-Krau...
[1, google translate] https://www-heise-de.translate.goog/newsticker/meldung/Schlo...