Boulder-based Socialthing, a service that lets users manage their online identity, has raised $300K of a planned $500K seed round from eonBusiness, according to the company’s blog. Still in private beta, the site is described as a central place to manage one’s profile across multiple social networking sites, while keeping on top of friend’s activities. Of course, lots of startups are doing some variation of this right now, in response to the problem, real or perceived, that users are overwhelmed by all of the various services out there. SocialThing was incubated out of the TechStars program; fellow alum MadKast, a maker of blog sharing tools, also raised $300K from eonBusiness earlier this month. Release.