Little Snitch gives you control over your private outgoing data.
Track background activity
As soon as your computer connects to the Internet, applications often have permission to send any information wherever they need to. Little Snitch takes note of this activity and allows you to decide for yourself what happens with this data.
Control your network
Choose to allow or deny connections, or define a rule how to handle similar, future connection attempts. Little Snitch runs inconspicuously in the background more...
WHAT\'S NEW
Version 3.3.1:
Improved dealing with large amount of silent mode suggestions.
Improved Little Snitch Configuration sidebar: Added explanatory texts.
Little Snitch Network Monitor Inspector performance improvements.
Little Snitch Network Monitor respects “Reopen windows when logging back in” option now.
Improved handling of certain VPN more...
REQUIREMENTS
Intel, OS X 10.6.8 or later
http://www.obdev.at/products/littlesnitch/index.html