If you're an avid Twitter user, you've probably experienced the frustrations of trying to use their built-in search. Ever since the deal between Twitter and Google ended in 2011, it has become extremely difficult to search through tweets to find what you're looking for, with the way Twitter serves their search results favoring more recent and more popular tweets.
Topsy has indexed billions of tweets – 425 billion of them to be exact – and has now made all those tweets available for searching.
While some of the features are only available in their Topsy Pro tool, they do make available some search data from tweets for free. The Topsy Pro version contains more advanced search abilities, as well as analytical data.
If you've been a Twitter user for years, one of the most interesting features of the Topsy search is that you can go back in history and see your first tweets and how long ago they were. Simply type "from:username" and sort by oldest, and you can see your first tweets. You can also use this to see the first tweets from other people you follow. For example, the first tweet from Matt Cutts was six years ago when he tweeted "fed the cats. they were hungry!"
Twitter is already using Topsy to power some of their own tools, including the Twitter Political Index and the Twitter Oscars Index so it's unlikely that Twitter will pull the plug on allowing Topsy access to index all the tweets, as it did with Google.