yeast washing?

I've seen a lot on here about washing yeast, but cant find anything about it in palmer or papazian. How do you go about doing it? And what are the benefits?

Thanks, good write up and just what I was looking for.

In short, washing yeast is a way that will allow you to store it for a short while and reuse the yeast. Yes, you can pitch onto a fresh yeast cake but in almost every instance this is over pitching onto stressed yeast. (Bob wrote a HUGE article about why we should not pitch onto a cake.) Building a starter from washed yeast is generally considered the "right way".

I have actually chosen to start a frozen yeast bank. I am just finalizing the area and equipment.