Just one quote from history.txt (the description of code changes in CVS):
- BUY_PERSONALISE flag support for item_stats of 'blank' items that are
bought from a merchant and then 'personalised' by the buyer; such
initial items being blank maps and books which get renamed, e.g.
"Book of <name>".
So clearly, writing your own books should be possible in the future, but that probably takes many more comments in history.txt
