How do I donate something to your cause to say thank you for the work you've already done (and for putting it online for free)? Paypal/Bitcoin would be easiest, but anything will do. :)
If you want to back that up with cash, the best way will be to buy a copy of the print version when it's out. Part of the magic of self-publishing is that I get a very large cut of the sales of that, so it's a good way to say thanks. (And you get a physical book out it!)
