All The Old Tweets Are Found: Google Launches Twitter Archive Search
The post below does rather assume that you already have a FriendFeed account of course...
If you have a FriendFeed account and your Twitter feed is on it, simply use the following syntax to find your old tweets - I've found my first ever tweet on there (Jun 08) so it seems the tweets persist for a while.
eg FriendFeed from:jobrodie will find any of my tweets (or posts I've made to FriendFeed) where I've mentioned the word FriendFeed.
There are a couple of people I'm following on Twitter who often post really useful interesting links that I might want to catch up with later. Favouriting individual tweets is one way but it's not that great a method for searching them retrospectively, but FriendFeed is.
If that person (or automated RSS feed, eg from a newspaper - it doesn't have to be an individual) isn't on FriendFeed, but their Twitter feed isn't locked - then you can add them as an 'imaginary friend' and follow them on FriendFeed that way. Then you can search their tweets.
Here's how (it assumes you have a FriendFeed account!) - mine's themed in 'Steampunk' colours.
1. Go to http://www.friendfeed.com, log in, and look for your Friends list
2. Click on the Browse/edit friends link, highlighted in lime green below.
3. Click on the Imaginary friends link (highlighted in magenta below).
4. Then click on the self-explanatory button - Create imaginary friend.
5. You are then asked to name the imaginary friend - I've called mine "DiabetesTrials" - and then clicking 'Create' will do precisely that.
6. The next page gives you an option to add different feeds - it could be Flickr or pretty much anything that is RSSable, but just click on the Twitter button (highlighted in orange below) to add a Twitter feed.
7. Add in the name of the Twitter feed - in this case it's DiabetesTrials and press 'Import Twitter'.
8. The new Twitterfeed appears in the 'Active Services' (highlighted in lime green below) and you can add more by repeating the process. If you want to see the tweets that @DiabetesTrials has posted, click on their name, highlighted in magenta in the pic below.
10. To search for an old tweet use similar syntax to that above - the significant difference is that 'DiabetesTrials' is not on FriendFeed and so you can't use the from:DiabetesTrials bit.
Instead you need to use friends:jobrodie eg:
Note the circle in green in the pic above, it's highlighting a padlock, which is next to any imaginary friend's feed - these are locked.
Anyone other than me will not be able to see the posts from such a locked, imaginary friend feed, it's only visible by me. Though there's nothing to stop you creating an imaginary friend for DiabetesTrials yourself (and I won't know about it).