Preferably something like Harry Potter’s, only with The Clapper© attached (because you actually have to find the damned thing to use it, right?) I’ve no idea how Harry always knew just where his was… 1
Anyhow, given the surveillance society we live in, wouldn’t it be nice to do certain things without every Tom, Dick and Harry spying in? Of course it would!
Enter some intrepid University of Texas researchers and their brand new material – metascreen!
Made of metascreen a cloak would shield you from view. Though, to be fair, right now you would have to be the size of a leprechaun for it to work. Give them time, give them time.