i just found a cool tool and i thought i share it here, it may not be what you want though. since it is used for contribution to open-source projects:
https://tip4commit.com/Dogecoin uses this:
https://github.com/dogecoin/dogecoin you can see the small image under the Icon.
also other projects using it:
https://tip4commit.com/projects~display that on a private url page.~
you do realize that when you accept a donation through a bitcoin address then there is nothing private about it.