Well 'per active' can actually have a lot of meanings depending on who you talk to but in essence, its a good business model for companies wishing to offer cheap trials whereby the affiliate doesnt actually get paid until the member has rebilled once or, not cancelled their membership for a certain period of time, for example 2 weeks, thats 'per active' in its basic form.

Single content billing, would be some system akin to iTunes, whereby a surfer loads an account with 'credit' and gets to use those credits to purchase individual scenes, days of access, or some other type of limit based on how the program sets access up, for example, say $5 buys the surfer 5 days of access to a site, or selection of sites or content.

Another form of single content billing would be for you guys to implement some kind of 'cart' system whereby content providers could load up a basic cart system with scenes, or image sets each with their own unique price point...

15 minute j/o scene $3.50
100 images $4
etc

The surfer/member/customer could then select X number of items and the 'total' value would then be processed via their credit card.

All of these are good ways to start moving adult memberships away from the regular 30 day recurring billing model whilst still allowing site owners and content producers to monetize their traffic effectively.

As i say, unless current billing models can be expanded to adapt to the growing concerns from porn surfers in how they are getting billed, a lot of consumers will be lost and as a billing company, you guys are in the perfect position to develop new billing mechanisms and implement them for the good of all our businesses.

I have to admit though, im actually suprised you dont already offer PPC as an option, you have all of the data needed it would simply be a case of setting up an additional payout option in WebAdmin, you count raw clicks, unique clicks and payouts/joins anyway, just combine that data to offer a PPC payout set by the program owner.

Regards,

Lee