I've just done my end of year donations to the following organizations: ArchLinux, @KDE, Firefox, Hubzilla, @FSFE and the Internet Archive. Just a small contributions to a few of the projects that I depend on, and that I think are important. There's so many more that deserves some support, but funds are limited. Perhaps the list will look different next year.
A note to those who wants to receive donations, however: Make it easy to donate! Some of the orgs above have made it really easy, notably @FSFE and the Internet Archive. All the others had issues with card payments. While I want to support your work, my patience with giving out money is limited.
Don't assume I am OK with registering an account anywhere to make a donation. Paying with debit/credit card is ok, so is an IBAN/BIC account for direct bank transfers. No, I will not register an account on paypal or anywhere else to donate money to you. Somebody else will get that money instead.
Also you might want to consider if you really need my postal address and phone number, and tell me clearly why you need that. I will not provide valid data in these fields unless I have a good rational reason for doing so. Afaik, you don't have one so stop requiring me to enter it.
It may be a good idea to try the donation process yourself. Donate some money to yourself, and see where the snags are.