If you assume that your friends on FriendFeed an Twitter are Mahalo style editors, how would you get that data via search so that it could be in a FrindFeed/Twitter client?
Both FriendFeed and Twitter apis have access limits that would hamper searches. But, what if you did not have to go through the apis? Than you could do much searching as you desired.
Search via using the site google operator only gives accurate data if you click on a cache page link see
Indiana Earthquake on FriendFeed and
Indiana Earthquake on Twitter.
However, you could bootstrap using Yahoo Pipes if you settled for only taking say a snapshot of the feeds daily or however recent the user might want. While getting FriendFeed individual feeds is simple such as my
seesmic search on my own feed, it would take some programming to get a yahoo pipe that could transverse the OPML format provided by FriendFeed and than search each feed of your friends.
Twitter is somewhat easier to get the friend feed as in
the help doc here. Which means a less dense Yahoo pipe to construct.
This would be a neat mashup to do and integrate in with a FriendFeed/Twitter client.