A Flattr intern and I were discussing a Pay by Facebook button and we made a point that in order for Flattr to scale, it would need better integration into popular services. Before putting a Flattr button for comments, just integrate it into Disqus so that anyone with Disqus on their blog can now receive Flattr donations. http://ericelias.posterous.com/facebooks-credits-will-trump-...
People on Disqus need to have a flattr account first, though. Preferable, people without an account would receive a message that people wanted to send them money for their comments, when people tried to flattr them.
It's easily doable - the only thing holding it back is Disqus's desire to innovate. So let's do our best to make sure it lands in Daniel Ha's desk.
It could also be interested to see it on some forums - but I'd worry that people might get an incentive to game the system. The same might apply to Disqus to some extent - go for the low-hanging fruit in a very partisan-lenient political discussion for instance. It might work on forums if it was only possible to flattr the opening posts and the work that went into making them. Gated forums where people are admitted at the admins' discretion might also make this work.
