Optimizely - A/B testing you'll actually use.
Proctor by Indeed - Proctor is a A/B testing framework written in Java.
Adobe Target - Adobe Target provides an intuitive user interface and an expanded personalization toolset.
Pagewiz - An innovative landing page platform that lets you create, publish, and split-test landing pages.
AB Tasty - AB Tasty is an all-inclusive platform for conversion rate optimization, personalization, customer activation, and testing.
invesp Pii Testing Engine - invesp Pii testing engine offers A/B testing solution for site optimization.