I had to get an important, expected call, so did what I NEVER do - picked up phone on an unknown number. Sorry I did so. I said hello twice, then when I heard someone on the line, I said, rather gruffly, "What is it?" The male imbecile on the line said, "Aw, shut up dude." I told him to indulge in sexual intercourse with himself (I used slightly different words, though,) and hanged up the phone. I hope I didn't miss the call I was waiting for!!
I should also say here that if it says "Out of Area" or "Unknown Name" or as in this case, "Wireless Caller," I let my landline machine pick up the phone and if it's someone I want to talk to, I'll THEN pick up the phone. The "Out of Area" ones have never... repeat... never even attempted to leave a message, so I KNOW they were would have wasted my time. Call @ 4:38PM on June 12th.

Picked up because we were expecting a call.  Boiler room noises in the background, female voice pushing
air conditioning tuneup, etc.  Told us she represented "Quality Air" located in Canoga Park, CA.
We have never done business with this outfit so told her she was violating the DNC List. Rude reply.
Caller ID says "Wireless Caller" so boiler rooms are now having their stooges use their own cell
phones to avoid detection.  There is no "Quality Air" listed in Canoga Park.  Scum

I just had the exact same experience!! I said "can you please remove this phone number from your list" after he took his time to respond and then he said "definitely not. we'll give you a call tomorrow".

They know  your name and want to talk to you about their air conditioning.

I had an obviously black woman spewing some kind of unintelligible angry crap but pretty sure she said something about 'dying.' Geeze.