Power Mac G4

The Power Mac G4 debuted in late 1999 and was the first Macintosh to be dubbed a supercomputer, capable of doing more than a billion calculations per second. The computer was later discontinued during the Summer of 2004.

Export limitations
At the start and for about a year after the late 1999 debut, the Power Macintosh G4 was not available for the market in the mainland of the People's Republic of China, as the US government deemed the "supercomputer" a "weapon". Mainland Chinese users, however, were able to get their hands on a Power Mac G4 after this limitation was removed. When the Titanium PowerBook G4 -- the first portable supercomputer -- was released, no similar sanctions were in place.