You might be interested in learning more about Priceonomics (http://priceonomics.com/ http://priceonomics.com/), a company does price comparisons for a bunch of

You might be interested in learning more about Priceonomics (http://priceonomics.com/ http://priceonomics.com/), a company does price comparisons for a bunch of stuff. I don't know what their engine is written on but it's certainly something custom, and that's most likely the way you want to go. They also have an amazing blog (http://blog.priceonomics.com/ http://blog.priceonomics.com/) where they showcase products and nifty stuff they do with them. They use Tumblr for this part of the site but you might as well go for Wordpress or whatever you prefer. No matter what you choose, you want to separate both parts of your site, and the comparison engine will most likely be a custom solution (Ruby, Python, PHP, doesn't matter).