Everyone except one person forms into pairs, they then have their legs tied together. The other person is then blindfolded and spun around, while the others scatter. The blindfolded player then has to try and catch one of the three legged groups, when they do they swap places with one of the two in the group they just caught.(One variation is they have to identify both of the three legged pair to swap or another is whoever they identify first becomes the blindfolded player)
Source: From the original site.(Submitted by: Harry)