Here are some TMNT phone charms that I recently purchased from Japan (it'll probably be at least two months before I receive them, alas).
This kind of item is often bootlegged, so it's hard to tell if these are official without holding them in hand. Whether or not they are official, these items appealed to me because they are obviously molded after drawings done by AC Farley, one of my favorite TMNT artists. NinjaTurtles.com actually used to use these drawings on the profile pages of each Turtle.
You can also check out a back view and an alternate front scan.