I was browsing cnet's news and I noticed that they posted some photos of the Collosus rebuild project. In the blurb, they failed to mention that the British had built several more of them for redundancy and increase throughput... and of course each later one carried improvements from the previous. If you're ever near Milton Keynes, it is worth spending a day at Bletchley Park. There is a computer museum there which has many working old computers, including an IBM PC model 5150, similar to the first PC that I owned. The Sinclair ZX-81 doesn't count as that belonged to my dad.