Here is how the SDL people do it.

http://www.libsdl.org/finances.php

I kind of like this format personally. It very much resembles a banking record book or online statement.

There are 'Anonymous' donors in the list as you can see. I'd have to look into how PayPal processes incoming donations to get a better idea of how a person can opt-out to putting up their name. But I'm sure it's entirely possible if they prefer to go unnoticed.