A recent addition to the anonymous calling service family is Jaxtr. This service lets you give it up to three real phone numbers and then let people reach you by clicking on a button
or widget
which you can place on you blog, web site, or any of several social networking sites. A key differentiator is that they have figured out the html to copy and paste into a large number of sites, including:
as well as generic web pages and email.
By default, the first call goes to voice mail, but then the recipient can go to a log of all received calls and allow specified callers (determined by CallerID) to get through.
Voice mails can be played from the web site and are alerted via email.
The service lacks the two-way anonymous return path of Jangl but in return is somewhat simpler to use.
I predict there will be a lot more of these services in the future and that we are only at the beginning of what is possible.