Andreessen's Palo Alto, Calif.-based start-up 24 Hour Laundry, which has about 14 employees, earlier this week launched Ning, describing it a free online service for building "social applications."
Company executives refer to Ning as a "playground" for creating content, such as photos and reviews, and sharing that information to connect with other people. The Ning site hosts these "social applications" and gives Web developers tools to build programs, either from scratch or by cloning existing services.
The CEO of 24 Hour Laundry is Gina Bianchini, who co-founded the company with Andreessen. The company's FAQ page, however, says Ning's goal is "to see what happens when you open things up and make it easy to create, share and discover new social apps."
Featured applications this week include a way to share book reviews, tips on San Francisco Bay Area walking trails and profiles of superheroes. On Thursday, Ning was the No. 1 search item on Technorati, where bloggers parsed the site's features and drew comparisons with other social-networking sites.
Ning aims to replicate the features of social-software sites such as Craigslist, Wikipedia and Flickr, where people can tag their photos and share them with others.
Ning, however, is appealing heavily to Web developers, with the idea that they can help increase the number of customizations and available services.
"The difference between apps built on Ning and any of these other services is that we make it easy for developers to build whatever app they want for any topic, interest, group, language, location or product, without a lot of effort. As a user, you get to explore and take advantage of this wider variety of social apps," according to the FAQ.
Ning intends to make money from advertising and premium services.
The company now allows developers to create a beta account. The development kit is oriented primarily for the PHP scripting language and other Web technologies, such as RSS and XML.
One reviewer, developer and designer, Frederico Oliveira, said in his blog that the ease of application creation from Ning is "as exciting as giving a box of Legos to a bunch of kids. That's what Ning may be. Legos for Web-apps."
Another reviewer, Java developer Chris Justus, said Ning has the potential to be sort of a clearinghouse for code that could be easily shared among programmers.
"I have no doubt that what they have created has the possibility to change the framework in which Web applications are created and delivered," Justus wrote in his blog.