I tried the hissing thing last night while trying to read. The new kitten came up to bother me by playing with the book's pages, chewing, pouncing when I turned the page, etc.
Finally I looked at him and hissed! You should have seen the look on his face! Stopped him cold. After a few beats, he climb up on my chest and wanted to be petted, the n he left me alone. and went down to the end of the bed and entertained himself.