Advanced Google Adwords - An in-depth look at using AdWords effectively
Q-Stats - Get free marketing insights for every question on Quora.
AdNabu - AdNabu is a Google Ads PPC automation software.
BiggerCake - The data tool that Kickstarter deserves
Opteo - Opteo searches for statistically significant patterns in an account and creates "optimization tasks" to improve account performance.
Campaign Monitor Insights - Actionable analytics for email marketing and automation