Effin Amazing UTM Builder - Add UTM tags to your links from a Chrome Extension
a.placebetween.us - Find a meeting point based on place type
UTMBuilder.net - Easiest UTM tags builder
Zenly - Zenly is a GPS tracker to locate your friends in realtime.
InterestExplorer - Discover 1000's of hidden Facebook interests to target.
Works For All - Find a central meeting place for everyone in the group