Twittospheric let you see in real-time all tweets about any topic like if you were in the twittosphere!
It's a fun & cool way also to explain to your friends what is Twitter ;) with an original visualisation of the new tweets, there, up in the higher skies!

You can follow the public timeline: http://twittospheric.com
or follow one user: http://twittospheric.com/oprah
or search for keywords: http://twittospheric/s/twitter