Here is a quick and easy DIY flash diffuser. The dimensions I'm sharing are specifically for the Sony NEX 5 but you can apply the same concept to almost any flash. I figure this is a good DIY craft for this time of year, since it's the holiday season and the days are shorter so it's likely that you'll be taking a lot of family/friend photographs in darker settings.
black craft foam
white craft foam
craft knife or scissors
cardboard/chipboard or surface for cutting on