Ever since I got an iPhone I have been plagued with calls from telemarketers and bill collectors looking for the previous owner of my phone number. I had gotten to the point where they were calling 10+ times a day. At first I would just let it go to voicemail but after a while I just wanted to make them stop calling. I then ran across youmail.com, which is a visual voicemail service for mobile phones. What I immediately liked about it was that you could assign different voicemail greetings to certain numbers. For instance, if a certain 800 number telemarketer keeps calling, just assign them the disconnected number greeting. After their autodialer hears the disconnected tones, your number is removed from the database. Bye bye telemarketing calls. I also set up a new contact in my iPhone contact list called telemarketers and assigned them a silent ringtone. That way I never hear the ring and it goes straight to the voicemail. Now my junk calls are down to 1-2 a week. Soon I have a feeling they will completely disappear. Now if I could just do something about SMS spam... Edit: I forgot to mention that there is a free youmail app that lets you check your voicemail on your iPhone. Works like a champ.