That still leaves a lot of space, so what I've decided to do is pack it out with a cheap biodegradable material - popcorn. I got a kilo bag of the grain yesterday, and I have a hot air popper. It looks like I can easily make enough to fill out the box with bags of popcorn, and since its made with hot air, not oil, it isn't greasy or smelly. The only hard part is not eating huge amounts!
This isn't actually a new idea - back in the seventies / eighties I think Dell or one of the other computer companies did this. But everyone went over to commercially made pellets filled with insecticides etc. or the plastic crap. For a big company that's obviously easier - for me I think the old method will work fine for a one-off package.
Just letting the machine cool a little before I make the next bag. Mmmmm, popcorn....
In other news there has been nothing more from calculator guy - I think he's decided that I'm not going to fall for his con, especially since I kept telling him that he needs to do this via eBay and the Italian post office and police. It's now nearly two months since I sold it, four weeks since it was delivered, and almost three weeks since he claims to have opened it, and I only give a 14-day returns warranty, so I think the boat has sailed. We'll see what happens.