Usability?

I’m on a couple of usability lists and one of them sparked a slightly strange exchange of messages a few minutes ago:

> 8:00:01 (in fact 8:00:00 + 1/infinity seconds) That would be 8:00:00 + (the smallest increment that the clock measures). You can't divide an integer by infinity. (Nor a rational number, nor an irrational number, nor a complex number, etc. -- for those who would quibble that I have limited it to integers :-)

So what did we talk about before we had the internet?