For my son's birthday he is having 25 children attend.  I did not want to spend a fortune on goody bags for 25 children.  I went on the orientaltrading.com web site and purchased simple neon plain sport water bottles for around 1$ a piece, and I bought paint markers (waterproof and permanent) and creatively wrote each child's name on a bottle.  Now each child attending will have a personlized favor they can take home and ACTUALLY use.