On my latest site I tried a highly optimized SEO approach (at least IMO). For my products, instead of linking straight to Amazon, I used a redirector page to which I feed the product name. But instead of an ID, I feed it a string such as "casablanca_1942_on_blu_ray". My redirector (buy.aspx) immediately redirects to the amazon page. This is all pretty straight forward, no questions asked. However, due to having an entirely new domain and watching the indexing actively, I found out that this page is actually being indexed as domain.com/buy.aspx?title=casablanca_1942_on_blu_ray but it also shows the actual amazon title and description which looks like the image below. It was fairly unexpected. (I'm new to the CPA game). And I thought some other people may find this of interest. as it looks like a straight amazon link if someone searches and clicks via a search engine, but you still get credited for it.