Amazon the web retailer has started to offer cash to bloggers who drop the name of specific products in their posts. The pay rate is based on how many click-throughs you get from your blog to an embedded link to Amazon. This, of course, causes partiality which some would say is hazardous to the free-minded world. That said, if I were to sell promotions on this blog, then I would clearly identify the pay-to-say sections. But from my point of view, it'd take a lot (and not pennies or dimes)for me to sell out my audience.
(note that name-dropping in content-enbedded ads is different that a general sponsorship or advertising that is kept separate from the journalistic material).