Claimed to be general manager from Commonwealth Bank, saying a bank to bank transfer to my account had been put on hold. Didn't give him time to explain more, just told him I do not have a Commonwealth bank account, and in no incertain terms told him he was a dirty low down stinking scammer and hung up.

spam

Caller: Pretended to be Telstra

Claimed to be Telstra. Saif they had been observing that our internet connection had been running slow for the last couple of days.
Told me she was calling to upgrade our lows speed internet to a high speed connection.
I lied and told her I already had a high speed connection (knowing that Telstra shoulkd know more than me about the connection) ...

I think this stumped her.

She said "OK" and hung up :-)