This activity either comes from a book called "Keep Talking " or one called "Grammar Practice Activities", (I can't remember which) both published by Cambridge and written by Penny Ur. Or, I should say, this is how I remember it. GOAL : To review many structures. To allow free talking in pairs. To practice asking follow-up questions. To do some group bonding. AH! Shucks! 
LEVEL: Any.
GROUP SIZE : Minimum 6 people. More people, more interesting.
TIME : 25 minutes minimum.
AGE GROUP: Adults or adult-like teenagers ie. any group who can do pair work with little supervision.
PREPARATION : A list of 10-12 sentence stems on topics that interest your students. Topics that allow a range of answers work best. One copy per student.
MATERIALS : Worksheets. Chairs. A bell or timer. METHOD
1) Prepare a list of unfinished sentences and give one copy to each student in class.
2) Allow 10 minutes or so for students to complete, in writing, the sentences using true facts about themselves.
**Check for comprehensibililty before starting pair work.
3) Arrange chairs in two rows, pairs facing each other.
4) Have students seat themselves with a partner. Tell them they will have 3 minutes to talk on the first topic.
5) Student A reads her sentence and student B asks more questions about it. Reverse roles.
6) After 3 minutes, ring a bell or clap loudly. Students must change partner and start on topic 2.
7) Continue rotating this way until all topics have been discussed
or every student has spoken with every other classmate.
FOLLOW UP : Return to normal seating arrangements and ask the group to remember and share the
most shocking, most unusual, funniest, etc. thing they learned about a classmate today. If time allows, discuss errors or prepare a correct-the-error worksheet for review next class.
POSSIBLE SENTENCE STEMS :
I have never ...
I'd like to visit ...
Some day I am going to...
I am happiest when I ...
I like people who...
I'd like to be more... and less ...
A good boyfriend/girlfriend/husband/wife will always...
Teachers/ Parents/ Kids should always ...
My favorite book is...
I have too many ...
I get very angry when I ...
If I could be anywhere right now I'd be ...
Studying English is ...