ThinkUp – Open-source app that stores your social network activity in a database

ThinkUp is a free, open source web application that captures your posts, tweets, replies, retweets, friends, followers and links on social networks like Twitter and Facebook.
 You can store your social activity in a database that you control, making it easy to search, sort, analyze, publish and display activity from your network. All you need is a web server that can run a PHP application.

Homepage: http://thinkupapp.com/