mike is right, and yes sputnik, i forgot to say you had to do at least one from each trick
well, another one then?
there are 1000 gnomes and a giant. the giant has locked up the gnomes in a cave. he said: i'll let you go one by one in another room. you may not talk and you have to stand in line. you will all get either a red hat or a white hat. when you're in line, i want all red hatwearing gnomes next to eachother and all white heatwearing gnomes next to eachother. so a 1000 gnome long line of first all red hats and then all white, or de other way around. when you enter the room, you have to pick a place in the line and may not change again.
then the giant ties the arms of all gnomes so they can't point where to stand. (these nots can only be untied by the giant)
as already mentioned the gnomes may not talk and have to stand still after they have chosen a spot. how do they solve this problem to get their freedom?