Examples of non-trivial roots of unity at ideal points of hyperbolic   3-manifolds
  This paper gives examples of hyperbolic 3-manifolds whose SL(2,C) character varieties have ideal points whose associated roots of unity are not 1 or -1. This answers a question of Cooper, Culler, Gillet, Long, and Shalen as to whether roots of unity other than 1 and -1 occur. 
Nathan M. Dunfield