He basically summed up the problem. You canâ(TM)t complain about PC culture because youâ(TM)ll be lumped in with Xists.

Lyons was a huge company. It didn't just make tea, it had a massive bakery division and also ran a very successful line of high street tea and coffee shops (think Starbucks - they were that common). It also did almost everything in-house - from vehicle maintenance to manufacturing its own machinery.

Finally, the company was seen as a very progressive concern - from the way it treated its workers (many of whom were women), through to adopting the latest business techniques - often from the US.

One of the original tasks was payroll automation - a huge task in a massive company with hundreds of pay grades and pre-decimalised coinage. But LEO came into its own when it was to process orders from these shops.

At the end of each day's business, managers would telephone a summary of their day's trading and their next order to Lyons HQ where the information was put on to punch tape and sent to LEO. The computer could then produce a collation of the orders to go to the bakeries, print dispatch slips, even generate a packing order for the trucks so that fragile items were added last!

LEO was even used to predict buying patterns - which foods were most popular at certain times of the year or in certain regions and ensure that supplies were ready for timely manufacture.

LEO was so successful it was then put to work for the government determining tax information for the Chancellor's budget and timetabling British Railways. Naturally it was such an advanced computer that it had to be killed off by one of the Labour Party's periodic bouts of nationalisation. The spin-off LEO Computers Ltd. was folded into the larger English Electric to become English Electric LEO, which then became English Electric LEO Marconi and finally ICL who eventually disappeared into the maw of Fujitsu.

There's an excellent book about LEO: 'A Computer Called LEO' by Georgina Ferry, ISBN 1841151866, Harper Collins UK, 2004. Well worth anyone's time. And the LEO project is remembered at LEO Computers Society.

The verification mechanism must have an error rate of less than 1 in 10 to the 38th power

10^38?

Because requiring an error rate of less than 1 in 10^39 is simply unreasonable to ask. ...and 1 in 10^37???? Well, jeez, might as well just build it out of matchsticks and glue if you're going to be THAT lax.

No, it's more like an address. Basically, the lines represent the period of a bunch of different pulsars and their distance from our sun. The idea is that if E.T. happens to know three (I think) or more of these pulsars, and happens to read binary, he might go "aha!" and find us and steal our water and/or women.