Apple has shipped Mac OS X Server, a new Unix-based operating system for high-end server use. Formerly codenamed Rhapsody, Mac OS X Server features the popular Apache Web server, Apple’s WebObjects, the capability to boot newer Macintosh models remotely via NetBoot, a high-performance Java virtual machine, network services such as DNS and Apple File Protocol, Web-based administration, and a consistent Mac-like user interface. (See "New iMacs, New G3s, and Mac OS X Server" in TidBITS 462 for additional information.) Mac OS X Server runs BSD Unix 4.4 on top of the Mach 2.5 microkernel (which together offer preemptive multitasking and protected memory), plus features application technologies originally acquired from NeXT. Mac OS X Server reportedly includes the Blue Box application layer, allowing Mac OS X Server to run standard Mac OS applications. By all reports, the Blue Box isn’t intended to allow Mac OS X Server to act as a workstation or to run current Mac OS server software. Developer support for Mac OS X Server is growing; several companies have already announced plans for Mac OS X Server, and more are sure to follow. Apple has priced Mac OS X Server aggressively at $499, with an unlimited client license; Apple is also selling 400 MHz G3-based servers with Mac OS X Server pre-installed starting at $4,999 (which Apple says is the fastest Apache server platform available for under $5000).