Cobalt Networks was a maker of low-cost Linux-based servers and server appliances. The company had 1,900 end user customers in more than 70 countries. During the dot-com bubble, the company had a market capitalization of $6 billion despite only $22 million in annual revenue.

In 2000, the company was acquired by Sun Microsystems and in December 2003, Sun shut down the Cobalt product line.