Microsoft made an announcement that they are extending the support of its Windows XP for Nettops which are low-power PCs. The announcement was at the Computex 2008 event.
This means that Nettop computers will have Windows XP Home Edition installed on them even after June 30 which is the last day that Microsoft will let Windows XP be installed on higher-end computers.
Nettop is a low-configuration PC with low-power consuming components according to the article at Techtree. It is a term that was cointed by Intel.
The extension for XP’s shelf life is also available on other machines, not just on Nettops.