Pig Latin in sign language

Is there any equivalent of Pig Latin in any signed languages? That is, some simple, regular way of obfuscating word forms to conceal their meaning from those not familiar with the transformation rules? If so, what sort of transformations are done on the gestures?

I know that there are similar games in written and spoken languages besides English, but I’m curious as to how such a system would work in a language which uses only gestures.