You know those plastico one's that have the nice attached lid and come sectioned? I get Chinese food and always ask for an extra. They make great sead starter containers and the top keeps everything moist and warm.
Oh and you write on the cover with permanent marker the date, seeds planted, etc. Every year, I look at those seed starter kits and just keep the containers I get for take out a few times a year. They are like little greenhouses!!! : )