What is StartThis? It’s Larry Sanger‘s microblog.
What’s a microblog? It’s like a Twitter-style social media feed, but it’s published on your own web domain, and it puts your posts in RSS format (which is super-cool).
The idea for StartThis (and many, many more microblogs like it to come) were published in this blog post.
The neat theme and related functionality are funded by a philanthropist, who donated the money for the project, which the Knowledge Standards Foundation is administering.
The software for this is demo’d here, and it will be open sourced and made widely and freely available, as soon as a mature first version has been developed.