i'm with verizon and for alot of people this might work good for you.Under your security settings set it where only"contacts only" can ring your phone.What is so good about this is the fact that if someone calls you from a phone# that is not stored in your cell phone the person will be directed to your voice mail and if it's someone really legit really needing to talk to you they'll leave a message and your phone will notify you that a voice mail was left,whats better is the fact that your phone doesn't even ring when the idiots call and most likely they won't leave a voice mail anyway,so far i've reduced unwanted calls on my unlisted cell phone to zero"0".Just set your incoming calls to "contacts" and leave outgoing and messaging set to "allow all".works for me!.Again this blocking feature works on the device it self and anyone calling from whatever number can atleast leave a voice mail message instead of ringing your cell phone device like grand central station.By the way,even by my cell phone not ringing it will log calls that were blocked and i can quickly check that on my cell phone just to see if it's a number i might reconize,but i only check that at the end of the day.
 Jun 29th, 2012
When I picked up the receiver, at 6:13 p.m., and said "yes," they hung up. I don't usually pick up, but I've been getting too many spam calls lately, and I was curious to see who was calling. This appeared on the caller I.D.: V409-181-32600052. I've never seen anything like that before.

On a few other number look-up sites, people have reported that it's marketing electronic cigarettes.
 Apr 10th, 2012