Last month, one of my partners made an application before the New Brunswick Court of Queens bench for an unusual ex parte order for the preservation and production of the contents of plaintiff's Facebook account. The order and reasons are here: Sparks v. Dubé, 2011 NBQB 40 (CanLII).
It's an unusual situation, which is well summarized by Dan Michaluk: Court Grants Ex Parte Order to Preserve Facebook « All About Information.