I wait for the answering message and if it turns out to be someone(or want to talk to...) I know I pick up. if not, I just ignore it. I also check the caller ID.

yeah, mine seems to be the common route...

you can always go on youtube and figure out how master pranksters deal with telemarketers...

figure out who they want to talk to and then say they're not here... otherwise say i'm not the one to talk to over such matters.

We have caller display but I still end up answering anyway 8D;
I always take the piss out of the way they asked for my mum (because they usually call her the wrong name) and then they hang up XD;; when I think about it, it seems really mean but I do it automatically XDXD
Poor telemarketers..what an awful job..

I answer in a different language to scare them off.
They usually hang up if I answer in Japanese xD;;

if a telemarketer calls. i tell them to take me off the list of calls. Then, they have no choice and they don't call again

Answer and laugh at them xD

I do't have call display so I pick up D:
and if they try to start selling me something or whatever I actually listen to what they say or whatnot and they say that I'm not interrested or whatever because I'd feel bad if I didn't TT-TT *woss*