Interesting, how does it work at a lower level?
For example, you want to reward question or answer author on the Rugatu. This user enters his address on the post page (for example, locate it below body text input). You must add affiliate address attribute to the DB table (or create separate table, which would contain, for example question ID as foreign key and payment address).
Let assume that someone opens a page with this question. You must fetch affiliate address from the DB and append it to the iframe request, e.g.
<iframe scrolling="no" style="border: 0; width: 468px; height: 60px;"
src="http://coinurl.com/get.php?id=1&share=<?php echo $affAddress; ?>"></iframe>
Then PHP session being created and fetched address will be temporarily associated with this ad slot. If an ad was clicked, a script on the CoinURL server will get a share rate (which you have specified in the ad slot settings) from CoinURL DB and insert record in the click table, which contains its price, share rate and affiliate address.
Each day, after we have performed fraud detection procedure, legitimate clicks will be marked as paid and summary values of the click cost multiplied by share rate will be sent to affiliate address, residuals (sum((1 - share rate) * click cost)) will be paid to your CoinURL account balance.