Optimizely - A/B testing you'll actually use.
AtroPIM - AtroPIM is a free, 100% open source and configurable PIM solution. It's easy to keep catalogs up to date, add new products or change existing ones, deliver your current product information across all channels.
Google Analytics - Improve your website to increase conversions, improve the user experience, and make more money using Google Analytics. Measure, understand and quantify engagement on your site with customized and in-depth reports.
Pimberly - The most powerful Product Information Management platform on the planet.
VWO - Use VWO to tweak, optimize & personalize your website with minimal IT help.
Bluestone PIM - Sales depends on how well you present your product.