A friend of mine responded to an ad like that, and it was two brothers who decided to be rock stars, despite a total lack of talent or experience.
My friend (a keyboardist with a degree from Berklee) left after about five minutes.
So I got their address from him, and for fifteen years, every few months or so I'll send them postcards from Biff and Muffy, a couple of successful musicians I made up, with stuff about their fights, psycho meds and their three horrible children, which they take on tour with them.
I'll make reference to some facet of the brothers' sad, boring lives (the town they live in, local clubs, local news stories, etc.) and I always tell them about life on the road, playing huge concerts, and never fail to mention a biker bar in the next town over from them.
I've never said anything threatening or weird in the slightest (that would spoil the surreal quality, I feel). I've also never told them the name of the act.
Hey, you have to do something. Might as well make it something funny and weird, huh?