Half way there

With 4 challenges complete there are a still 226 of you at the top of the leaderboard, maybe Challenge 5 will start to separate the pack a bit! (Maybe not, I will be veeeerrry (how should I spell that?) interested to see what happens this week.) Anyway well done to everyone. We still have teams taking part, including one from Honolulu. (There are other "illegal, but we'll turn a blind eye" entries from Australia, New Zealand, Singapore, China, Japan - zoom out on the map on the front page to see.) Have fun, Harry