There was a discussion... some time ago (maybe even a few years ago, actually), regarding a hypothetical web service where users deposited funds (say, a few dol

There was a discussion... some time ago (maybe even a few years ago, actually), regarding a hypothetical web service where users deposited funds (say, a few dollars at a time) and enabled it on websites of their choosing. When they loaded a website, it could check if the user had that installed and enabled for their website. If so, it would charge them a microtransaction (a few cents, etc) and not load ads. If they did not, it would load ads. In this way, they paid services they used frequently as they used them and in increments they didn't mind. Of course, there is a lot of things undefined in this model about how it would be implemented, but it was an idea I still think has merit.