> .... What I really want to know is - why do our two Honda cars each have the windscreen wiper on different sides of the
steering wheel. I can cope with different makes being different but the same make! Anyway, I digress ...

Now you really go too far, Jo! Check out this website to satiate all of your curiosities: http://www.howthingswork.com/

It may not contain everthing you want to know but it's a pretty cool site.