I've been using the one from Griots Garage for the past 4 winters (my last car as well as the Crossfire) and its GREAT! Its got a computer chip inside of it that detects when the battery is fully charged and then turns itself off and then when needed, turns itself back on. Its a quality piece and comes with terminal clips as well as "alligator" style clips incase you don't leave it on all that long.

www.griotsgarage.com