This is the box for the first Mac OS X (10.0 and 10.1). Its design is simple, but tells a story about its user interface. Mac OS X introduced the world to Aqua, all glass, shininess, and transparency. It was the flashiest, most apparent feature of the new operating system—which was a complete departure from the old and decrepit Mac OS 9. The box big X showed exactly that.
This was the first retail box that acknowledged the code names of Mac OS X. The first two versions were Cheetah and Puma, which omitted any official mention to the big cats. Jaguar fully embraced the codename game, so much that Apple commissioned Pixar to render the X as actual jaguar fur in glorious 3D, using one of their famous Renderman procedural shaders (no photos or textures, just math here). You can count the hairs, and it looks so naff it is cool.
Panther moved into the new design of the company's products, which came with the latest iPods and computers. The X was embossed and chromed. It looked nice and sleek.
Tiger followed the same trend. Smaller packaging, but bold, simple, and with great production. It was also the last big box, before they reduced all their software packaging drastically, to the CD jewel box size.
Leopard was the most aggressive of them all, using a cool design tied to one of the main features of the new OS version: Time Machine. It has it all: Good design, sleek black, and holographic eye candy. The highest point before the Snow Leopard smlehness.
I can haz clip art? Come on, Apple. What's wrong with you?