IBM is coming over all nostalgic after honouring a 1950s era supercomputer, that it modestly calls "one of the most significant systems of the computer age." Too bad, the machine was considered a flop at the time.

It was fifty years ago this week that IBM built the Stretch supercomputer, and IBM marked the event on Thursday with a retrospective at the Computer History Museum in Mountain View, California, attended by three of the system's pioneers: Fred Brooks, Fran Allen and Harwood Kolsky.

The project was something of an audacious gamble for IBM at the time. It had hoped to create a "monster" computer that was 100 times faster than the current IBM supercomputer (the 704). In the end, it was only 30 to 40 times faster than the 704.

The first system was developed for the Los Alamos Scientific Laboratory under contract to the Atomic Energy Commission. It was delivered in 1961, and cost an eye watering $13.5 million (£7.5 million), although this was later dropped to $7.78 million due to its failure to meet its aggressive performance estimates.

Yet the Los Alamos National Laboratory association with IBM continues to this day, and they built the world's first petaflop machine back in June this year, a supercomputer named Roadrunner, designed to ensure the safety and reliability of the nation's nuclear weapons stockpile.

Despite some sales, Big Blue readily admits the Stretch supercomputer was not a commercial success in its era. Less than 10 were built and the project was shelved. Yet Big Blue insists that Stretch remains noteworthy, simply because of the innovative technologies it used, such as multitasking, which enables a computer to juggle more than one job at a time, is still being used today.

Stretch also contained pipelining, or lining up instructions in a queue, so that the computer doesn't have to wait between operations.

Another feature was memory protection to prevent unauthorised memory access - crucial in providing computer security. It also had memory interleaving, which broke up memory into chunks for much higher bandwidth. Incidentally, the memory in Stretch was immersion oil-heated/cooled to stabilise its operating characteristics.

Stretch also used the eight-bit byte - establishing a standard size for the unit of data representing a single character.

The machine itself was packed with 150,000 transistors and could perform 100 billion computations a day - making it the world's fastest computer back in 1958.

Despite the commercial flop of Stretch, its technologies went into feature in something a bit more successful for Big Blue, namely the System/360 mainframe.