A few magazine articles that I wrote (years ago) were translated into other languages, but none of my books has ever been translated … until now. The Inform 7 Handbook is being translated into Italian! I can’t read Italian, but the first chapter (at http://milleuna.sourceforge.net/docs/GuidaInform7.pdf) looks to be very good.
The fact that I uploaded the Handbook both as a PDF (for easy reading) and as an OpenOffice document (for easy editing) allows Leonardo Boselli to keep the document formatting. I imagine it might make it easier for him to do the translation, as well.