Forthcoming 0.2.5 release allows the searching of tweets (thanks to Bram), from Twitter and Identi.ca.

Seeks regroups tweets that look very similar and puts them on top of the result list. In application, this means that Seeks identifies most of the retweets (RT) of a given tweet. Therefore the most retweeted tweets come first in the list of results.

Seeks allows clustering of tweets. This automated tool puts tweets with similarities into the same group and renders the groups on the screen. This can be useful for sorting many tweets with similar hashtags but dissimilar contents.