StatCounter - StatCounter is a simple but powerful real-time web analytics service that helps you track, analyse and understand your visitors so you can make good decisions to become more successful online.
V12 Data - V12 Data offers rich data sets with verified addresses and emails for personalized marketing campaigns.
Histats - Start tracking your visitors in 1 minute!
Adobe Audience Manager - Adobe Audience Manager is a data management platform that integrates online and offline data to deliver a unified view of all your audiences
AFSAnalytics - AFSAnalytics.
Google Audience Center - 3 votes and 6 comments so far on Reddit