Photos: What should be crowned the king of Apple cool?

4: Mac OS X

The OS X operating system took its time emerging from the wreckage of the Copland project. But the next generation OS has won a new set of fans for the company. Although it took until version 10.3, known as Panther, to really come of age, Apple's crown jewels have won it plaudits for usability, design élan, stability and interoperability. Now on Leopard, version 10.5, it's hard to think of a more complete, fully featured operating system on the market. OS X is now inside the iPhone, too, and it's likely to underpin everything Apple does over the coming years. A recent personal reversion back to OS9 showed how far the company has come in just a few short years.

Photo credit: Apple

See what Apple's got up its sleeve for 2008 at this year's Macworld