Been on one of these in the Carribean (Jamaica) and its a hoot. Kinda of expensive, but most of the tours are over priced anyway. Just don't forget to look around while you are zipping. And you better not be afraid of heights. One of my daughters almost backed out, it took a lot of convincing to get her to go, but once she did the first "zip" she got past the fear for the fun of the zip... I imagine that the Alasaka ones are bascially the same.. you only need some tall trees to do this with.
Carnival Cruise Lines:
Fantasy 90, Celebration 95, Victory 05, Conquest 05, Spirit 6/06, Freedom 6/08, Holiday 7/08, Victory 6/09, Valor 9/09, Dream 6/10, Splendor 8/10,Conquest 8/11,Magic 11/11,Triumph 4/12,Spirit 7/12,Freedom 11/12, Triumph 2/13 - The fire cruise
NCL Dream October 2006, RCCL Mariner OTS June 2007