I just got a call which I will add to my block list. I will now get no ring but will get a list of blocked calls on my phone.
I have the Panasonic cordless telephone Model kx-tg6842b (2 handsets)
You can block 250 numbers plus kill the one ring that existed on earlier models that only allowed 30 blocked numbers.
The one handset model sells for $70 at Amazon.

I had never heard of Operation Smile.
 Nov 13th, 2013
Professional fundraisers, so could be calling for any political or charitable group. Treads on the dark side of telemarketers in their methods.
 Oct 25th, 2013
Telemarketer Arlington VA. Added to my NUISANCE calls
 Jun 19th, 2013
My dad made a donation once. That's all it takes to be on their list. My dad passed away 2 1/2 years ago. No need to call any more.
 Mar 10th, 2012