Wikipedia states:

A network computer is a lightweight computer system that operates exclusively via a network connection. As such, it does not have secondary storage such as a hard disk drive – it boots off the network, but runs applications locally, using its own CPU and RAM. This set NCs as distinct from terminals, which act as a client for an application server.

During the mid to late 1990s, some commentators and industry players such as Larry Ellison of Oracle Corporation, predicted that the network computer would soon take over from desktop PCs, and that many users would use applications loaded via a network instead of having to own a local copy.

So far, this has not happened, and it seems that the network computer “buzz” was either a fad or not ready to happen. The NC can be considered to be another computing paradigm. Just as PCs did not replace mainframes, so NC will not replace PCs. The new technology provides a more appropriate alternative in certain areas and can co-exist with established systems through open standards.

Google has just announced an even-thinner paradigm, Google Apps for Your Domain:

… a set of hosted applications for organizations that want to provide high quality communications tools to their users without the hassle of installing and maintaining software or hardware.

Given that GAFYD is a browser-based version of the network computer, one wonders if history is destined to repeat itself.