OSX Developer Preview 2 (Rhapsody 5.1 Circa 1998)
Rhapsody was the code name given to Apple Computer's next-generation operating system during the period of its development between Apple’s purchase of NeXT in late 1996 and the announcement of Mac OS X in 1998. It consisted primarily of the OPENSTEP operating system ported to the Power Mac along with a new GUI to make it appear more Mac-like. Several existing Mac OS technologies were also ported to Rhapsody, including QuickTime and AppleSearch. Rhapsody could also run Mac OS 8 in a “Blue Box” emulation layer.
Its odd, When compared to OS X Server 1 this Developer Preview feels a little more polished in some places and yet in others Terribly rudimentary.
The Pull away menus are kinda my favorite interface convention that never made it to the Final released of OSX.