Greatest (clean) put-downs

What are the best put-downs you use or have heard, without sinking into obscenities and even keeping the moral high-ground?



I've had trouble with phone-scammers and phishers calling nonstop lately, so I've had some practice. They call nonstop. My favorite is just to calmly inform them "I feel sorry for your parents." That always shuts them up quicker than cursing them out.



What's a good, but polite way to put someone down?