Here's a new one.
I had a call from Vodaphone and once I recognised it was telemarketing (clue: they had no idea who they were speaking to) I said "No thanks."
They said "I'm not selling anything, I'm just offering you the opportunity to minimise your calls from Vodaphone if you'll answer a few questions about your mobile phone account."
Telemarketers are now making threats?!
"Answer the questions now, or we'll just keep on calling... you wouldn't want your business to keep getting interrupted would you...?"