Hurstwic is a Viking-age reenactment group in New England which plays a reconstructed version of knattleikr at some of their events.
Unstated, but evident, in the Hurstwic reconstruction is the notion that knattleikr is a member of the football family. As in football games, a ball is to be transported to the end of the field to score; unlike most, the players are also equipped with sticks, which are used both to start the plays and to impede the progress of opposing players. Given their placement of knattleikr in relation to other games, it's a great reconstruction - simple, but with the essence of the family in place, and with rules that make sure the ball will periodically be struck with the sticks and fly across the field.