Found during an idle browse – Mr. McGroovy’s Box Rivets which are little plastic rivets you can use to stick cardboard together. We’ve had lots of success giving the boys (2.5 and 5 years old) cardboard boxes and building stuff with them, enjoyment which is slightly marred by the fact that sticking them together is hard. Now, we don’t have to worry! Looking forward to them coming – pleasingly, they’re setup to ship to Europe too, which is an encouraging trend.