Interesting idea. I hope to at least see more like this, even if this fails. What I'd really like is to be able to tip articles, posts, apps, and websites. I don't frequent the New York Times enough to justify a subscription, even despite the annoying nagging full-page interstitials. I don't think giving them a percentage of my ad revenue would be worth it, but if I could tip a few quarters when I came across an article that I thought was really well done, I would gladly do so.

I think if you gamified a system like this, it could really do well. It'd need to be cross-site, since it'd be cool to compare to my friends and see who they tended to support the most. It wouldn't have to directly show the donation amounts; it could be translated into some arbitrary other point system and include other incentives to get bonus points. Basically, make it a high-score / prestige thing.