A few things that seem to work for me...
1st days of school
I make a friendship web using yarn. We all get into a circle and each student states their name. (In my school, the students are fairly familiar with most of the other students, but may not remember their names). Then the game begins... I'll go first stating my name. Then, holding a portion of the yarn, I toss the ball across the circle calling out a student's name. That student must say my name, their name, then another student's name (who then will get the ball of yarn). That new student has to say my name, the 1st student's name, then their name. They then call out another name and throw the ball of yarn to that person. Each student continues in this way holding onto a part of the string before throwing it. In the end, they have built a friendship web and learned the names of their classmates, too.
"Me in a Bag"...
Kids bring in a paper bag with about five things that really say something about them. It could be a picture of their family or pet, a trinket from vacation, etc. Then at school, each child gets 3 minutes or so to explain each of the items in the bag. Its a great way for their classmates me to find out the students' interests.
Personalized name tags...
I set up a set of directions for the students to follow to design a name tag for the front of their desk. Just some examples of the steps: If the student has a birthday in Jan.-Apr. they get a yellow strip of paper, May-Aug. gets white, Sept.-Dec. gets light blue. They write their names in the middle large enough for visitors to see from the front of the room with their favorite color. In the upper right hand corner they a draw simple picture of their favorite food, upper left hand corner, they draw symbols to represent sisters and brothers ( a circle with a face and long hair - sister, short hair - brother).... You get the point. When they're finished, they get together in partners or small groups and trade name tags going through each one by one "reading" the symbols to find out more about their new friends.