While everyone with an e commerce site would love to provide rich customer comments and “if you like this, then you’ll like that” cross-selling, it takes money. Usually lots of it.

At least until now. PowerReviews lets you add product reviews and referrals to your site . . . for free. It works more or less like Amazon, but with some interesting twists. First, they have a system set up to identify which reviews were completed by someone who actually purchased the product (verified buyers). Next, they’ve built their system to work on simple tags (complete a review of the Barbie Backpack Fishing Kit to see how tagging changes the experience), making it faster to complete a review and making it easier for readers of the review to figure out if the review applies to their needs or not (e.g., is this mountain bike for casual riders [see section labeled describe yourself]). Finally, they offer what they call Affinity reviews and recommendations to help you find the product that’s preferred by people like you (see how this works when shopping for a digital camera).

Of course, there’s no free lunch. In return for this free service, PowerReviews gains the right to aggregate all review data and present it on their own review site, Buzzillions. In any case, if you’ve thought that Amazon-style reviews and referrals were just out of reach - think again.