The BBC just ran a story about the TrueCall, a device developed by a group of British eggheads sick and tired of receiving unwelcome phone calls. The idea behind the device is quite brilliant, though not particularly original: numbers on a user-created white list go through normally, numbers on a black list receive a snippy recorded messages and unidentified callers must wait on hold while the end user decides what to do. Ad blocking browser plugins and some spam email filters work in much the same way.

With that idea in mind, it struck me that some kind of iPhone application might be able to do something similar. The iPhone, with its works (almost) anywhere Internet connection, could download a list of known telemarketers' phone numbers and display the incoming call to the end user depending upon its status. Then I remembered that Apple has yet to grant developers that kind of system-level access — namely the ability to tinker with the Phone application — to make such a system possible. Unfortunate.

In the interim, someone — perhaps me if I have enough time — should put together a plugin for Mac OS X Address Book that syncs one huge vCard file with the name "Telemarketer" and known telemarketers' phone numbers between Macs and a user-created telemarketing blacklist in the cloud. I would never need to answer another junk phone call again. Unfortunately, there's no way to have the iPhone answer the call and play a pre-recorded message.