Lol I remember this.
This was horrible. I was in front of a couple of people while doing it trying to work out which ones I was supposed to get and which ones I wasn't. I think in the the end I got 31/40, which didnt seem to raise any suspicions thankfully. Someone nearly bet me some money I couldn't get them too :D.
edit: that one's pretty good Blue Tornado. Unfortunately I got interrupted...