Answer on: What about extending the donation and payment system on flattr?
Flattring without funds is pretty pointless as you should give to show your appreciation. But I think what you're asking for is already there. You can login to flattr and in there "Add funds" and use lots of systems to reload your flattr account - and also use money you got from people flattring you - which is what you're asking for if I understand right. It's hard to find if you never click on "add funds" of course ;-)
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