Double the cores? Double the fun?

Back in the dim and distant past when dinosaurs roamed the Earth, I worked with some people from the research branch of a computer manufacturer. Some of the people who worked for this company told me of a project that had been undertaken by some of their colleagues. This project became one of their higher end computer models a few years later.

What they had done was taken two of their Unix based (non-intel) computers and connected them together by flipping some of the bus cables between the two halves. This involved writing some additional drivers as well but worked well enough that it eventually became a commercial product.

Now, as I am not made of money this strikes me as an interesting problem, but I would rather try something like this with cheaper computers (the up-core for example) rather than the sort that they used. I realise for actual compute power it would be easier to just buy a bigger computer, and probably cheaper. But this is more like climbing Everest...

So, does anyone else think that this would be possible? Would it be interesting to try? Or am I just going senile in my old age.

Z.