Recently I typed Ctrl-D in Konsole in order to exit the current shell. Instead, I got a dialog for adding bookmarks :-(
Ctrl-D
Konsole
This was after upgrading to Kubuntu 8.10. To fix this, edit ~/.kde/share/config/kdeglobals and change
~/.kde/share/config/kdeglobals
AddBookmark=Ctrl+D
into (for example):
AddBookmark=Ctrl+Shift+B