Searching for relevant information on Twitter can be a frustrating exercise, and if you are looking for anything other than the  most recent posts on a topic, you may be out of luck entirely.

PostPost is a search engine for Twitter that lets you search historical posts from the people you follow most.  It searches up to 200 of your follows, and you can easily navigate to posts from just a particular individual.  You can also filter for only postings with links, or postings with photos.  PostPost indexes not only the 140 characters in a Twitter post (aka tweet), but also content from links being shared.  Your past searches are saved, so topics you look for regularly are easy to find – you can even save links to read later.

The service is free, and you need to sign in with your Twitter account.  You can read more and view a quick video tutorials on the PostPost homepage.