>When I took the school filter off for him to go browsing about it, he Tweeted to his friends that he'd "hacked the network". This was a top-class, privately-educated kid.
You know full well the last thing he wants to do is change his machine. Identifying the best theme for his browser is the last thing he wants to HAVE to do.
The Wikipedia link in the summary says "Despite its size and density, the patch is not visible from satellite photography."
I'd suggest that's nonsense, and it's precisely the lack of density that prevents it being noticeable as a defined area in satellite shots.
Actually, there's a loophole here. If you don't pay your phone bills, your BT service will be disconnected, but the broadband line continues to work. (Optional for the conscientious: Then settle the outstanding debt with BT, but don't ask to be reconnected.) I've done this in all my last three places, worked fine until I moved out, two years in one case, nearly a year in the other two. Bethere.co.uk in all cases.