YoruFukurou 2.1

YoruFukurou (NightOwl) is a native Twitter client for Mac OS X.
You can filter tweets by defining rules with user IDs, keywords, and regular expression.

The tabs are highly configurable, so you can tailor the application to your own needs.
It is also possible to remove the filtered tweets from your timeline.
You can also create tabs from Lists.
You can create a tab that shows search results from Twitter Search. This type of tab can be used to search from the entire Twitter, instead of just your timeline.