Game to see how well people think they know each other and the group
pens and paper
Split the group into teams (at least 4 teams, but the more the better) each with a pen and some paper.
Ask a series of questions, for example "Who is most likely to become Prime Minister", "Who is most likely to represent their country at sport", "Who is most likely to appear on 'Britain's Got Talent'". etc. (be as imaginative/surreal as you like)
After each question, all teams write down the name of 1 person in the room and all answers are collected in. Assuming the same answer appears more than once, then ALL the teams who picked the MOST POPULAR answer score a point (i.e. if 3 teams wrote down "Steve", 2 teams wrote "Helen" and 1 team wrote "Bruce"; then ONLY the teams who wrote "Steve" will score a point), if 2 or more answers are tied for being the most popular, then decide if you want to award a point for each, or half a point, or just ignore that round (similarly if every team gives a different answer then just ignore that round).
The winner is the team with the most points after all the rounds. The game will also work with everybody writing down answers as individuals, but it will be more fun when teams (of 2 or more) are trying to agree on their answer.