Today, I added pingback support to this blog. Pingbacks have been around for years, but for some reason I just became infatuated with them. Basically, it was one of those things I always wanted to learn more about but never set aside the time.
Movable Type introduced trackbacks, which are reportedly more prone to spam. Trackbacks were built around the REST model, whereas pingbacks use XML-RPC for requests (i.e., pingbacks seem to be better). Though, as you're well aware, people will find a way to spam anything.
In case you're drawing a blank on XML-RPC:
[XML-RPC is] a spec and a set of implementations that allow software running on disparate operating systems, running in different environments to make procedure calls over the Internet.
Right now, I only accept incoming requests, but I plan on adding outgoing requests. Nevertheless, I built my "server" off the Incutio XML-RPC Library and had it up and running in under an hour.
In the coming months, I plan to launch Very Helpful, a resource site for web developers. It will be much like the resource sites around the web, except I hope to cater to the middle of the development spectrum (i.e., the intermediate knowledge level). Moreover, I hope to provide code that can be freely used in Flash and PHP projects—basically, an open source resource in the vein of the new Webmonkey. That said, my pingback implementation will be made available there.