From our blog dedicated to magic words and symbols spotted in the wild:
The Lord of Misrule, magician/comedian Tommy Cooper, sometimes intoned an "incomprehensible incantation of dubious foreign extraction that might have been spelled 'Zhhzhhzhhzhh,' but probably wasn't" (John Fisher, Tommy Cooper: Always Leave Them Laughing, 2006, p. 6).
[Thanks, Jonathan!]